Install Helm without third-party setup action

.gitea/workflows/chart.yml

@@ -16,9 +16,17 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-      - uses: azure/setup-helm@v4
-        with:
-          version: ${{ env.HELM_VERSION }}
+      - name: Install Helm
+        run: |
+          set -euo pipefail
+          curl --fail --silent --show-error --location \
+            --output "${RUNNER_TEMP}/helm.tar.gz" \
+            "https://get.helm.sh/helm-${HELM_VERSION}-linux-amd64.tar.gz"
+          tar --extract --gzip --file "${RUNNER_TEMP}/helm.tar.gz" \
+            --directory "${RUNNER_TEMP}" linux-amd64/helm
+          mv "${RUNNER_TEMP}/linux-amd64/helm" "${RUNNER_TEMP}/helm"
+          chmod 0700 "${RUNNER_TEMP}/helm"
+          echo "${RUNNER_TEMP}" >> "${GITHUB_PATH}"
       - name: Lint, render and validate the chart
         run: ./test.sh
 
@@ -30,9 +38,17 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-      - uses: azure/setup-helm@v4
-        with:
-          version: ${{ env.HELM_VERSION }}
+      - name: Install Helm
+        run: |
+          set -euo pipefail
+          curl --fail --silent --show-error --location \
+            --output "${RUNNER_TEMP}/helm.tar.gz" \
+            "https://get.helm.sh/helm-${HELM_VERSION}-linux-amd64.tar.gz"
+          tar --extract --gzip --file "${RUNNER_TEMP}/helm.tar.gz" \
+            --directory "${RUNNER_TEMP}" linux-amd64/helm
+          mv "${RUNNER_TEMP}/linux-amd64/helm" "${RUNNER_TEMP}/helm"
+          chmod 0700 "${RUNNER_TEMP}/helm"
+          echo "${RUNNER_TEMP}" >> "${GITHUB_PATH}"
       - name: Select immutable chart version
         run: printf 'CHART_VERSION=%s\n' "$(./scripts/chart-version.sh)" >> "$GITHUB_ENV"
       - name: Package and publish chart