Fixing some issues on RIT workflow

Issues fixed:
1 - Remove the trigger on push for master  and *-rc -> we don't need that
anymore since we are running it for every commit on PRs against these branches.

2 - Solve the issue that the status of an execution triggered via workflow doesn't update the PR status.
 And if we need to use a different branch for RIT, Powpeg and RIT in the PR, it won't change the status to
 green after the workflow_dispatch execution -> We will do that adding a parsing on the description, looking
 for the branch that need to be used for that PR. If there is no branch configured on the description, we will
 try to use the default one.

.github/workflows/rit.yml

@@ -1,8 +1,6 @@
 name: Rootstock Integration Tests
 
 on:
-  push:
-    branches: ["master", "*-rc"]
   pull_request:
     types: [ opened, synchronize, reopened ]
     branches: ["master", "*-rc"]
@@ -17,27 +15,57 @@ on:
         required: false
         default: 'master'
 
+env:
+  REGEX_PARSE_BRANCH: '([a-zA-Z0-9/_-]+)'
+
 jobs:
   rootstock-integration-tests:
     name: Rootstock Integration Tests
     runs-on: ubuntu-latest
     timeout-minutes: 60
     steps:
+      - name: Fetch Pull Request Description
+        id: fetch-pr-description
+        uses: actions/github-script@v6
+        with:
+          script: |
+            const pr = await github.rest.pulls.get({
+            owner: context.repo.owner,
+            repo: context.repo.repo,
+            pull_number: context.payload.pull_request.number
+            });
+            
+           return pr.data.body;
+          result-encoding: string
+      - name: PR description fetch
+        run: echo '${{ steps.fetch-pr-description.outputs.result }}'
+
       - name: Set Branch Variables
         id: set-branch-variables
         run: |
           # Default values
           RSKJ_BRANCH="master"
           RIT_BRANCH="${{ github.event.inputs.rit-branch || 'main' }}"
-          POWPEG_BRANCH="${{ github.event.inputs.powpeg-branch || 'master' }}"
 
+          # Set the RSKJ branch
           if [[ "${{ github.event_name }}" == "push" && "${{ github.ref }}" == "refs/heads/*-rc" ]]; then
             RSKJ_BRANCH="${{ github.ref }}"
           elif [[ "${{ github.event_name }}" == "workflow_dispatch" ]]; then
             RSKJ_BRANCH="${{ github.ref_name }}"
           elif [[ "${{ github.event_name }}" == "pull_request" ]]; then
             RSKJ_BRANCH="${{ github.head_ref }}"
           fi
+          
+          PR_DESCRIPTION="${{ steps.fetch-pr-description.outputs.result }}"
+
+          # Set the Powpeg branch
+          if [[ -n "${{ github.event.inputs.powpeg-branch }}" ]]; then
+            POWPEG_BRANCH="${{ github.event.inputs.powpeg-branch }}"
+          elif [[ -n "$PR_DESCRIPTION" && "$PR_DESCRIPTION" =~ fed:${{ env.REGEX_PARSE_BRANCH }} ]]; then
+            POWPEG_BRANCH="${BASH_REMATCH[1]}"
+          else
+            POWPEG_BRANCH="master"
+          fi
 
           echo "RSKJ_BRANCH=$RSKJ_BRANCH" >> $GITHUB_ENV
           echo "RIT_BRANCH=$RIT_BRANCH" >> $GITHUB_ENV