Add `coverage-reporter-platform` input option (coverallsapp#233)

* Add coverage-reporter-platform input option to control which architecture-specific version of coverage-reporter is downloaded and run by the github-action. 
* Since this option is not available for MacOS or Windows, we deliver warning messages if the option is set, but continue processing with default behavior. 
* We have also stepped back from returning exit code 1 when coverage-reporter-version is set on MacOS and, instead, now deliver a warning message and allowing processing to proceed with the latest version installed by Homebrew. 
* We have also added tests for different values of coverage-reporter-platform.
* We've added logic to handle the introduction of new platform-specific filenames available in versions from v0.6.15 up and the different contents of coveralls-checksums.txt to be backwards compatible with versions <= v0.6.14.

Add `coverage-reporter-platform` input option (coverallsapp#233)

* Add coverage-reporter-platform input option to control which architecture-specific version of coverage-reporter is downloaded and run by the github-action. 
* Since this option is not available for MacOS or Windows, we deliver warning messages if the option is set, but continue processing with default behavior. 
* We have also stepped back from returning exit code 1 when coverage-reporter-version is set on MacOS and, instead, now deliver a warning message and allowing processing to proceed with the latest version installed by Homebrew. 
* We have also added tests for different values of coverage-reporter-platform.
* We've added logic to handle the introduction of new platform-specific filenames available in versions from v0.6.15 up and the different contents of coveralls-checksums.txt to be backwards compatible with versions <= v0.6.14.

Always point the major version tag to the latest release (coverallsap…

…p#230)

* Add a workflow to always point the major version tag to the latest release.

Verify that `coverage-reporter-version` option is recognized (coveral…

…lsapp#229)

* Add test for coverage-reporter-version.
* Add logic to handle when coverage-reporter-version is empty, in addition to when it is null/unset.
* Apply fail-on-error logic to error when user tries to set coverage-reporter-version on MacOS (not available there).

Extend behavior of `fail-on-error` option to setup failures (coverall…

…sapp#226)

* Technically an enhancement, these changes make the action behave as many customers already expect by ignoring any and all failures when the `fail-on-error` input is set to `false`. 
* Adds logic to handle any failures in "setup" tasks, including downloading the associated binary, verifying the binary, and finding the binary by its expected name after extraction.
* The new logic checks these actions and exits with exit code `1` on failure, except if `fail-on-error` input is set to `true`, in which case it returns exit code `0`.
* Adds a matrix workflow that tests the action for each `os` and each key binary command (`report` and `done`). Each of these scenarios implicitly tests our setup tasks since they run first in each scenario.
* Extends the behavior of `debug: true` to flip the shell-specific debug flag for each `os` including `set -x` for `linux` and `macos` and `Set-PSDebug -Trace 1` for `windows`

2.3.0: Add optional coverage-reporter-version parameter

2.2.3: fix directory creation on Windows runners

2.2.2: use pwsh for windows runner

2.2.1: add measure, files, and fail-on-error options

2.2.0: allow globs in file option