Fix regression for creating repositories in root-based containers (#172)

Due to #160 it was no longer possible to create repositories in root-based containers. This was caused by the missing `/tmp/gitea` directory in that image. It was dynamically created by Gitea internal functionality with less privileges than necessary.

Explicitly creating the directory and set proper permissions fix this.

Fixes: #171

Co-authored-by: JustusBunsi <sk.bunsenbrenner@gmail.com>
Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/172
Reviewed-by: luhahn <luhahn@noreply.gitea.io>
Reviewed-by: 6543 <6543@obermui.de>
Co-authored-by: justusbunsi <justusbunsi@noreply.gitea.io>
Co-committed-by: justusbunsi <justusbunsi@noreply.gitea.io>

templates/gitea/init.yaml

@@ -23,6 +23,11 @@ stringData:
     chmod -R 700 /data/git/.ssh
     mkdir -p /data/gitea/conf
 
+    # prepare temp directory structure
+    mkdir -p "${GITEA_TEMP}"
+    chown 1000:1000 "${GITEA_TEMP}"
+    chmod ug+rwx "${GITEA_TEMP}"
+
     # Copy config file to writable volume
     cp /etc/gitea/conf/app.ini /data/gitea/conf/app.ini
     chmod a+rwx /data/gitea/conf/app.ini