Use unified Heroku buildpack output style

[Malax]

This PR introduces a new shared library for all JVM buildpacks that implements the unified Heroku buildpack output style. All buildpacks in the repository have been modified to use this new shared library over the log module from libherokubuildpack.

In some cases, the buildpacks changes their output a little bit more to output more detailed information about the process. For example, the jvm buildpack now tells the user where the OpenJDK version is defined.

Example

# Heroku OpenJDK Buildpack

- OpenJDK version resolution
  - Using version string provided in `system.properties`
  - Selected major version `11` resolves to `11.0.25`
- OpenJDK Installation
  - Downloading and unpacking OpenJDK distribution
  - Done (50.5s)
- Applying JDK overlay
  - Skipping (directory `.jdk_overlay` not present)
- Linking base image certificates as OpenJDK keystore
  - Done.

# Heroku Maven Buildpack

- Installing Maven
  - Skipping (Maven wrapper detected)
- Running Maven build
  - Running `./mvnw -DskipTests clean install`
    Picked up JAVA_TOOL_OPTIONS: -Dfile.encoding=UTF-8
    [INFO] Scanning for projects...
    [INFO]
    [INFO] -------------------< com.heroku:simple-http-service >-------------------
    [INFO] Building simple-http-service 1.0-SNAPSHOT
    [INFO] --------------------------------[ jar ]---------------------------------

Closes:
W-17215812
W-17215820
W-17215822
W-17215818

[schneems]

Not a blocker, but would help for QA-ing the output as a whole to print the getting started guide in CI. https://github.com/heroku/buildpacks-ruby/blob/187770e700a433cf9e6af678cb3eb5735b89eec5/.github/workflows/ci.yml#L62-L97

[schneems]

Please merge #761, put this back in draft state and make changes until you're happy with the output (removal of newlines, using the correct style for a "value" etc.) Then we can iterate on the output style. Happy to iterate/pair too.

[Malax]

All (still applicable) comments have been addressed. :)