Class not found: com.app.handler.AsynchronousLambdaHandler: java.lang.ClassNotFoundException, Current classpath: file:/var/task/

I have developed a spring boot REST API, trying to deploy it using serverless framework as a Lambda on top of API Gateway, and encountered the following the error

Class not found: com.app.handler.AsynchronousLambdaHandler: java.lang.ClassNotFoundException
java.lang.ClassNotFoundException: com.app.handler.AsynchronousLambdaHandler. Current classpath: file:/var/task/

I am using Spring Boot version 2.7.10, java version 11, maven as a build tool, and serverless as a deployment tool to deploy the application in AWS.

The handler class is available at BOOT-INF/classes/com/app/handler/AsynchronousLambdaHandler.class post-packing the application as a .jar file.

serverless.yml

service: integration-service

provider:
    name: aws
    region: us-east-1
    stage: ${opt:stage, 'dev'}

functions:
    "integration-service":
        handler: com.app.handler.AsynchronousLambdaHandler::handleRequest
        name: ${opt:stage, 'dev'}-integration-service
        runtime: java11
        memorySize: 512
        events:
            -   http: ANY /{proxy+}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.7.10</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.app</groupId>
	<artifactId>integration-service</artifactId>
	<version>1.0.0</version>
	<name>integration-service</name>
	<description>Integration Service</description>
	<properties>
		<java.version>11</java.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>
		<dependency>
			<groupId>com.amazonaws.serverless</groupId>
			<artifactId>aws-serverless-java-container-springboot2</artifactId>
			<version>1.9.2</version>
		</dependency>
	</dependencies>
	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
				<configuration>
					<finalName>${project.artifactId}</finalName>
				</configuration>
			</plugin>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-shade-plugin</artifactId>
				<version>3.2.4</version>
				<configuration>
					<createDependencyReducedPom>false</createDependencyReducedPom>
				</configuration>
				<executions>
					<execution>
						<phase>package</phase>
						<goals>
							<goal>shade</goal>
						</goals>
					</execution>
				</executions>
			</plugin>
		</plugins>
	</build>
</project>

AsynchronousLambdaHandler.java

package com.app.handler;

import com.amazonaws.serverless.exceptions.ContainerInitializationException;
import com.amazonaws.serverless.proxy.model.*;
import com.amazonaws.serverless.proxy.spring.*;
import com.amazonaws.services.lambda.runtime.*;
import com.app.IntegrationServiceApplication;

public class AsynchronousLambdaHandler implements RequestHandler<AwsProxyRequest, AwsProxyResponse> {
	private SpringBootLambdaContainerHandler<AwsProxyRequest, AwsProxyResponse> handler;

	public AsynchronousLambdaHandler() throws ContainerInitializationException {
		handler = (SpringBootLambdaContainerHandler<AwsProxyRequest, AwsProxyResponse>) new SpringBootProxyHandlerBuilder()
				.springBootApplication(IntegrationServiceApplication.class)
				.asyncInit()
				.buildAndInitialize();
	}

	@Override
	public AwsProxyResponse handleRequest(AwsProxyRequest input, Context context) {
		return handler.proxy(input, context);
	}
}

I have also explored a lot of options including this one (<https://stackoverflow.com/questions/72535951/aws-lambda-function-throws-classnotfoundexception-lambdahandler-current-class>) but no luck so far.

Edit:

Updated the pom.xml to remove maven plugins to simplyfy the problem.

pom.xml (updated)

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.7.10</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.app</groupId>
	<artifactId>integration-service</artifactId>
	<version>1.0.0</version>
	<name>integration-service</name>
	<description>Integration Service</description>
	<properties>
		<java.version>11</java.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>
		<dependency>
			<groupId>com.amazonaws.serverless</groupId>
			<artifactId>aws-serverless-java-container-springboot2</artifactId>
			<version>1.9.2</version>
		</dependency>
	</dependencies>
	<build>
		<finalName>${artifactId}</finalName>
	</build>
</project>