allow to pass custom base image tag to build

Author: Tofel

.github/workflows/k8s-publish-test-base-image.yaml

@@ -5,6 +5,11 @@ on:
       # we only need base image for k8s based tests
       - 'lib/v*'
   workflow_dispatch:
+    inputs:
+      tag:
+        description: 'Tag for the base image'
+        required: true
+        type: string
 
 jobs:
   publish_test_base_image:
@@ -19,12 +24,19 @@ jobs:
       - uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4.2.1
 
       - name: Strip "lib/" from github.ref_name
+        if: ${{ github.event_name == 'push' }}
         run: |
           stripped_ref_name="${GITHUB_REF//refs\/tags\/lib\//}"
           # disabling as the string containing variable is double-quotted as a whole, no need to quote each variable separately
           # shellcheck disable=SC2086          
           echo "BASE_IMAGE_TAG=${{ secrets.QA_AWS_ACCOUNT_NUMBER }}.dkr.ecr.${{ secrets.QA_AWS_REGION }}.amazonaws.com/test-base-image:$stripped_ref_name" >> $GITHUB_ENV
 
+      - name: Export base image tag for workflow dispatch
+        if: ${{ github.event_name == 'workflow_dispatch' }}
+        shell: bash
+        run: |
+          echo "BASE_IMAGE_TAG=${{ secrets.QA_AWS_ACCOUNT_NUMBER }}.dkr.ecr.${{ secrets.QA_AWS_REGION }}.amazonaws.com/test-base-image:${{ github.event.inputs.tag }}" >> $GITHUB_ENV
+
       - name: Build Base Image
         uses: smartcontractkit/chainlink-github-actions/docker/build-push@d2f9642bcc24a73400568756f24b72c188ac7a9a # v2.3.31
         with: