Shadowing is needed when integrating Agent with Spark 3.x versions

[benedeki]

Describe the bug

Dependency shading might be needed when using the Agent in Spark environment (especially when some Hadoop dependencies are in use as well, for example if you package the application that contains the Agent and use such JAR in Spark Submit command).

Expected behavior

Shading is not needed. The required libraries that needs shading are part of the Agent library already in shaded form.

Workaround (shading to add to the project)

Here's the suggested project code snippet for Maven:

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>${maven.shade.plugin.version}</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <relocations>
                        <relocation>
                            <pattern>okhttp3</pattern>
                            <shadedPattern>shaded.okhttp3</shadedPattern>
                        </relocation>
                        <relocation>
                            <pattern>okio</pattern>
                            <shadedPattern>shaded.okio</shadedPattern>
                        </relocation>
                        <relocation>
                            <pattern>sttp</pattern>
                            <shadedPattern>shaded.sttp</shadedPattern>
                        </relocation>
                        <relocation>
                            <pattern>cats</pattern>
                            <shadedPattern>shaded.cats</shadedPattern>
                        </relocation>
                        <relocation>
                            <pattern>shapeless</pattern>
                            <shadedPattern>shaded.shapeless</shadedPattern>
                        </relocation>
                        <relocation>
                            <pattern>kotlin</pattern>
                            <shadedPattern>shaded.kotlin</shadedPattern>
                        </relocation>
                    </relocations>
                    <filters>
                        <filter>
                            <artifact>*:*</artifact>
                            <excludes>
                                <exclude>META-INF/*.SF</exclude>
                                <exclude>META-INF/*.DSA</exclude>
                                <exclude>META-INF/*.RSA</exclude>
                            </excludes>
                        </filter>
                    </filters>
                </configuration>
            </plugin>