Switch Docker CI from gitlab to github

Adds buildx signing and helm chart publication.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

.github/workflows/helm.yml

@@ -0,0 +1,46 @@
+# release.yaml
+name: Release Charts
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Configure Git
+        run: |
+          git config user.name "$GITHUB_ACTOR"
+          git config user.email "$GITHUB_ACTOR@users.noreply.github.com"
+
+      # Optional step if GPG signing is used
+      - name: Prepare GPG key
+        run: |
+          gpg_dir=.cr-gpg
+          mkdir "$gpg_dir"
+          keyring="$gpg_dir/secring.gpg"
+          base64 -d <<< "$GPG_KEYRING_BASE64" > "$keyring"
+          passphrase_file="$gpg_dir/passphrase"
+          echo "$GPG_PASSPHRASE" > "$passphrase_file"
+          echo "CR_PASSPHRASE_FILE=$passphrase_file" >> "$GITHUB_ENV"
+          echo "CR_KEYRING=$keyring" >> "$GITHUB_ENV"
+          echo "sign: true" > cr.yaml
+          echo "key: Smarter Project" >> cr.yaml
+        env:
+          GPG_KEYRING_BASE64: "${{ secrets.GPG_KEYRING_BASE64 }}"
+          GPG_PASSPHRASE: "${{ secrets.GPG_PASSPHRASE }}"
+
+      - name: Run chart-releaser
+        uses: helm/chart-releaser-action@v1.4.1
+        with:
+          config: cr.yaml
+        env:
+          CR_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
+