Correct PR workflow to work for PRs from forked repositories #388

Job	Run time
dump-unicode-data / generate-dump	4s
collect-output-reviewdog	2m 50s
check-pr / check-style	3m 52s
check-pr / check-linux / check	3m 37s
check-pr / check-macos / check	5m 22s
check-pr / check-windows / check	4m 34s
	20m 19s

Provide feedback