Drone: Do full branch clone and get tags for correct version hashes (#6836)

Although #591 attempted to make version hashes be preceded with tag names on our branch builds, it would fail again silently at 50 commits because we were not cloning the full branch. Drone's new plugin will do a single branch clone by default meaning that depth is no longer necessary.

.drone.yml

@@ -2,13 +2,12 @@ workspace:
   base: /go
   path: src/code.gitea.io/gitea
 
-clone:
-  git:
-    image: plugins/git:next
-    depth: 50
-    tags: true
-
 pipeline:
+  fetch-tags:
+    image: docker:git
+    commands:
+      - git fetch --tags --force
+
   download_translations:
     image: jonasfranz/crowdin
     pull: true