docs: Gitea account must have full name set for Git identity (#16792)

* Gitea account must have full name set for Git identity

* Update lib/modules/platform/gitea/index.md

Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

* Update index.md

Co-authored-by: Michael Kriese <michael.kriese@visualon.de>
Co-authored-by: Rhys Arkins <rhys@arkins.net>

lib/modules/platform/gitea/index.md

@@ -14,6 +14,7 @@ Let Renovate use your PAT by doing _one_ of the following:
 - Set your PAT when you run Renovate in the CLI with `--token=`
 
 Remember to set `platform=gitea` somewhere in your Renovate config file.
+Either the account should have full name and email address set to allow Renovate to estabilish Git identity, or the `gitAuthor` config option should be set.
 
 ## Unsupported platform features/concepts