Add support to run gitea with an optional securityContext (#115)

Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/115
Reviewed-by: luhahn <[email protected]>
Reviewed-by: lafriks <[email protected]>
Co-authored-by: martencassel <[email protected]>
Co-committed-by: martencassel <[email protected]>

values.yaml

@@ -13,6 +13,8 @@ image:
 
 imagePullSecrets: []
 
+securityContext: {}
+
 service:
   http:
     type: ClusterIP