ci: Publishing and downloading flank scripts

[piotradamczyk5]

Fixes #1347

flank-scripts is now published to JFrog Bintray [1], so instead of building flank-scripts each time when running some workflow on GitHub actions or when you need it, you could just download it using simple gradle task[2].
flank-scripts support now versioning, so there is a requirement to update its version each time you changed some files inside flank-scripts directory, otherwise, detekt task will fail[3].
Each GitHub actions workflow is updated to download latest version instead of building flank-scripts to save time and resources.[4]

Test Plan

How do we know the code works?

[1]

1. Run gradlew :flank-scripts:bintrayUpload (bintray account needed)
2. Flank scripts should be updated on bintray

[2]

1. Run gradlew :flank-scripts:download
2. flankScripts.jar should be downloaded to flank-scripts/bash

[3]

1. Change some files under flank-scripts
2. Run gradlew check or gradlew detekt
3. Gradle task should failed (please notice that in current PR, version is updated)
4. Update version in flank-scripts/build.gradle.kts
5. Run gradlew check or gradlew detekt
6. Gradle task should succeed

[4]

1. Check if all workflows has replaced

- name: Gradle Build flankScripts and add it to PATH
        run: |
          ./flank-scripts/bash/buildFlankScripts.sh
          echo "./flank-scripts/bash" >> $GITHUB_PATH

to

- name: Download flankScripts and add it to PATH
        run: |
          ./gradlew :flank-scripts:download
          echo "./flank-scripts/bash" >> $GITHUB_PATH

Checklist

• Publish Flank-scripts to JFrog Bintray
• Create Github workflow which will make it after each push to master
• Create task to download latest version from JFrog Bintray
• Replace Github actions Workflow building to downloading flank-scripts
• Add method to prevent merging flank-scripts without version update

[codecov-io]

Codecov Report

Merging #1361 (f778dcd) into master (23b269b) will increase coverage by 0.02%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #1361      +/-   ##
============================================
+ Coverage     77.81%   77.83%   +0.02%     
  Complexity      705      705              
============================================
  Files           244      244              
  Lines          4693     4693              
  Branches        901      901              
============================================
+ Hits           3652     3653       +1     
  Misses          550      550              
+ Partials        491      490       -1     

[github-actions]

Timestamp: 2020-12-01 09:10:10
Buildscan url for ubuntu-workflow run 393473025
https://gradle.com/s/celdo2gus7oue

[pawelpasterz]

nit: Flank/flank

[piotradamczyk5]

👍

[adamfilipow92]

• Tested, upload/download works
• Code looks good