Add `removeJarVersionNumbers` build setting (#8116)

This is handy to enable consistent local version numbers rather than
updating file paths each release.

Add the following to enable locally `~/.gradle/gradle.properties`

```
removeJarVersionNumbers=true
```

CONTRIBUTING.md

@@ -36,6 +36,14 @@ and then you can find the java agent artifact at
 
 `javaagent/build/libs/opentelemetry-javaagent-<version>.jar`.
 
+To simplify local development, you can remove the version number from the build product. This allows
+the file name to stay consistent across versions. To do so, add the following to
+`~/.gradle/gradle.properties`.
+
+```properties
+removeJarVersionNumbers=true
+```
+
 ## IntelliJ setup and troubleshooting
 
 See [IntelliJ setup and troubleshooting](docs/contributing/intellij-setup-and-troubleshooting.md)

javaagent/build.gradle.kts

@@ -216,6 +216,12 @@ tasks {
     dependsOn(shadowJar, baseJavaagentJar)
   }
 
+  if (findProperty("removeJarVersionNumbers") == "true") {
+    withType<AbstractArchiveTask>().configureEach {
+      archiveVersion.set("")
+    }
+  }
+
   withType<Test>().configureEach {
     dependsOn(shadowJar)