chore(gh): drop task and call script directly

.github/workflows/proto-upgrade.yml

@@ -22,17 +22,14 @@ jobs:
         with:
           go-version: 1.19
 
-      - name: Setup go-task/task
-        uses: 'lagren/setup-task@v1'
-
       - name: Clone Flipt into sub-directory
         run: gh repo clone flipt-io/flipt
 
       - name: Bootstrap Tools
         run: |
           pushd ./flipt
           git checkout ${{ inputs.tag }}
-          task bootstrap
+          ./script/bootstrap
           popd
 
       - name: Buf Generate