ci: Replace set-output command with echo to GITHUB_OUTPUT
ci: Replace set-output command with echo to GITHUB_OUTPUT

The `set-output` command was deprecated. The new way to set an output
parameter for a step is to echo to the file stored in `$GITHUB_OUTPUT`

gitblit/gitblit,gitblit/gitblit,gitblit/gitblit,gitblit/gitblit,gitblit/gitblit