UI: Fix overflow issues in repo (#7190)

- Fix layout overflow in repo file list.
- Fix invisible status icon in file view and commit list. In file view,
  the icon was moved to the left because I could not figure out a proper
  fix because of HTML tables.
- Added title attribute to commit messages.
- Fixed two CSS linter warnings in existing CSS.
- Fixed CI variable check in 'make css'.

Fixes: https://github.com/go-gitea/gitea/issues/7180

Makefile

@@ -395,7 +395,7 @@ css:
 	npx postcss --use autoprefixer --no-map --replace public/css/*
 
 	@diff=$$(git diff public/css/*); \
-	if ([ ! -z "$CI" ] && [ -n "$$diff" ]); then \
+	if ([ -n "$$CI" ] && [ -n "$$diff" ]); then \
 		echo "Generated files in public/css have changed, please commit the result:"; \
 		echo "$${diff}"; \
 		exit 1; \