fix: prevent script injection in workflows (v0.11.x) (#640)

Fixes script injection vulnerability by moving github.event references
to top-level env vars.

Changes:
- Replace `github.event.inputs.version` with `env.VERSION` in run steps
- Reuses existing top-level VERSION env variable

Related to V1564738566

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choice.

Author: thpierce

.github/workflows/post-release-version-bump.yml

@@ -28,8 +28,8 @@ jobs:
 
       - name: Extract Major.Minor Version and setup Env variable
         run: |
-          echo "VERSION=${{ github.event.inputs.version }}" >> $GITHUB_ENV
-          echo "MAJOR_MINOR=$(echo ${{ github.event.inputs.version }} | sed -E 's/([0-9]+\.[0-9]+)\.[0-9]+/\1/')" >> $GITHUB_ENV
+          echo "VERSION=${{ env.VERSION }}" >> $GITHUB_ENV
+          echo "MAJOR_MINOR=$(echo ${{ env.VERSION }} | sed -E 's/([0-9]+\.[0-9]+)\.[0-9]+/\1/')" >> $GITHUB_ENV
 
       - name: Get current major.minor version from main branch
         id: get_version
@@ -86,8 +86,8 @@ jobs:
 
       - name: Extract Major.Minor Version and setup Env variable
         run: |
-          echo "VERSION=${{ github.event.inputs.version }}" >> $GITHUB_ENV
-          echo "MAJOR_MINOR=$(echo ${{ github.event.inputs.version }} | sed -E 's/([0-9]+\.[0-9]+)\.[0-9]+/\1/')" >> $GITHUB_ENV
+          echo "VERSION=${{ env.VERSION }}" >> $GITHUB_ENV
+          echo "MAJOR_MINOR=$(echo ${{ env.VERSION }} | sed -E 's/([0-9]+\.[0-9]+)\.[0-9]+/\1/')" >> $GITHUB_ENV
 
       - name: Determine release branch and checkout
         run: |

.github/workflows/pre-release-prepare.yml

@@ -53,8 +53,8 @@ jobs:
 
       - name: Extract Major.Minor Version and setup Env variable
         run: |
-          echo "VERSION=${{ github.event.inputs.version }}" >> $GITHUB_ENV
-          echo "MAJOR_MINOR=$(echo ${{ github.event.inputs.version }} | sed -E 's/([0-9]+\.[0-9]+)\.[0-9]+/\1/')" >> $GITHUB_ENV
+          echo "VERSION=${{ env.VERSION }}" >> $GITHUB_ENV
+          echo "MAJOR_MINOR=$(echo ${{ env.VERSION }} | sed -E 's/([0-9]+\.[0-9]+)\.[0-9]+/\1/')" >> $GITHUB_ENV
 
       - name: Create branches
         run: |