Add a toolchain only - control update of settings.xml, toolchains.xml, JAVA_HOME and PATH more granular

[mhoffrog]

09-Nov-2023: Amended commit comments only.

Description: The following input items have been added (copied from README.md update):

• update-env-javahome: By default action updates env.JAVA_HOME with the path of java installed. In order to skip update of JAVA_HOME, set this to false. The creation of the env variable JAVA_HOME_{{ MAJOR_VERSION }}_{{ ARCHITECTURE }} is NOT affected by this item. That will be created for any setup.

• update-env-path: By default action adds <java_install_dir>/bin to env.PATH. In order to skip this, set this to false.

• update-toolchains-only: If set to true, then overwrite-settings, update-env-javahome and update-env-path are propagated to false if the specific one is not explicitly configured to true. Only a toolchain entry will be added to toolchains.xml. Default is false.

Summary on a few code improvements (Inserted by 09-Nov-2023): By that implementation I did a few code improvements as follows:

• setup-java.ts:
  • renamed interface installerInputsOptions -> IInstallerInputsOption and moved the definition to the top of the source file to levarage readability
• input values for overwrite-settings - plus the ones I did add - are read now once only in a single code place (within setup-java.ts only) to a constant and pass their effective values either by method parameters or by object fields to other places during the runtime lifecycle
• variable naming within toolchains.ts
• minor improvements of wording on log messages regarding toolchains.xml updates.

Further particular details on the code changes can be taken from my commit comment https://github.com/actions/setup-java/commit/b0dadd279479dcb798d4d5ab673fbd3c27b7fb0b.

Related issue: #552

Check list:

• [x] Mark if documentation changes are required.
  :bulb: Documentation has been updated by this PR
• [ ] Mark if tests were added or updated to cover the changes.

[mhoffrog]

@IvanZosimov is there anything I can do in addition to get this PR merged?

[mhoffrog]

@IvanZosimov PR branch is re-based to current main and dist scripts did pass Check dist action.

[mhoffrog]

@IvanZosimov PR branch is re-based to current main and dist scripts did pass Check dist action.

[mhoffrog]

@mahabaleshwars @IvanZosimov FYI - PR branch is re-based to current main and dist scripts did pass action Check dist

[mhoffrog]

@mahabaleshwars @IvanZosimov FYI - PR branch is re-based to current main and dist scripts did pass action Check dist

[mhoffrog]

@mahabaleshwars @IvanZosimov FYI - PR branch is re-based to current main and dist scripts did pass action Check dist