chore(ci): revert version changes in release pipeline (#402)

* Revert version changes and add temporary changes for testing

* Bump helm version

* Revert to 3.5.4

* Return to hard-coded versions

* Revert to pinned version

* Revert temporary changes

Author: matthewelwell

.github/workflows/release.yaml

@@ -5,9 +5,6 @@ on:
     tags:
       - flagsmith-*.*.*
 
-env:
-  HELM_VERSION: v3.12.3
-
 jobs:
   release:
     runs-on: ubuntu-latest
@@ -21,7 +18,7 @@ jobs:
       - name: Install Helm
         uses: azure/setup-helm@v3
         with:
-          version: ${{ env.HELM_VERSION }}
+          version: v3.5.4
 
       - name: Add chart repo dependencies
         # Note: this repos should match with the repos set in ct.yaml
@@ -33,9 +30,9 @@ jobs:
           helm repo add bitnami https://charts.bitnami.com/bitnami
 
       - name: Set up chart-testing
-        uses: helm/chart-testing-action@v2
+        uses: helm/chart-testing-action@v2.0.1
         with:
-          version: ${{ env.HELM_VERSION }}
+          version: v3.3.0
 
       - name: Run chart-testing (lint)
         run: ct lint --config ct.yaml --lint-conf lintconf.yaml