feat: switch to github raw url for bitnami charts (#324)

Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/324
Reviewed-by: techknowlogick <techknowlogick@gitea.io>
Reviewed-by: justusbunsi <justusbunsi@noreply.gitea.io>
Co-authored-by: takirala <takirala@noreply.gitea.io>
Co-committed-by: takirala <takirala@noreply.gitea.io>

Chart.yaml

@@ -3,7 +3,7 @@ name: gitea
 description: Gitea Helm chart for Kubernetes
 type: application
 version: 0.0.0
-appVersion: 1.16.7
+appVersion: 1.16.8
 icon: https://docs.gitea.io/images/gitea.png
 
 keywords:
@@ -29,20 +29,21 @@ maintainers:
   - name: Steven Kriegler
     email: sk.bunsenbrenner@gmail.com
 
+# Bitnami charts are served from GitHub CDN - See https://github.com/bitnami/charts/issues/10539 for details
 dependencies:
 - name: memcached
-  repository: https://charts.bitnami.com/bitnami
+  repository: https://raw.githubusercontent.com/bitnami/charts/eb5f9a9513d987b519f0ecd732e7031241c50328/bitnami
   version: 5.9.0
   condition: memcached.enabled
 - name: mysql
-  repository: https://charts.bitnami.com/bitnami
+  repository: https://raw.githubusercontent.com/bitnami/charts/eb5f9a9513d987b519f0ecd732e7031241c50328/bitnami
   version: 6.14.10
   condition: mysql.enabled
 - name: postgresql
-  repository: https://charts.bitnami.com/bitnami
+  repository: https://raw.githubusercontent.com/bitnami/charts/eb5f9a9513d987b519f0ecd732e7031241c50328/bitnami
   version: 10.3.17
   condition: postgresql.enabled
 - name: mariadb
-  repository: https://charts.bitnami.com/bitnami
+  repository: https://raw.githubusercontent.com/bitnami/charts/eb5f9a9513d987b519f0ecd732e7031241c50328/bitnami
   version: 9.3.6
   condition: mariadb.enabled