only_check_changed_filed breaks with PR from fork in v0.0.22

[VictoriousRaptor]

When trying to run spell check job it raises an error and just exits. See here.

Config is here

[VictoriousRaptor]

So basically it fails when PR HEAD is in another repo. I believe it's because we set only_check_changed_filed to true.

 Only checking files changed from dev
##[debug]Skipped logging an issue for the matched line because the severity 'fatal' is not supported.
fatal: ambiguous argument 'refs/private/before': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
git fetch origin  'dev:refs/private/before' 'delay-restart-2:refs/private/after' -- failed:
##[debug]Skipped logging an issue for the matched line because the severity 'fatal' is not supported.
fatal: couldn't find remote ref delay-restart-2
git fetch . 'dev:refs/private/before' 'delay-restart-2:refs/private/after' -- also failed:
##[debug]Skipped logging an issue for the matched line because the severity 'fatal' is not supported.
fatal: couldn't find remote ref delay-restart-2
##[debug]Skipped logging an issue for the matched line because the severity 'fatal' is not supported.
fatal: ambiguous argument 'refs/private/before..refs/private/after': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'

The fetch tries to fetch a branch where is not at origin.

check-spelling/unknown-words.sh

Lines 1974 to 1983 in 697744a

	if ! git fetch -f origin ${UNSHALLOW:+"$UNSHALLOW"} "$BEFORE":refs/private/before "$AFTER:refs/private/after" > "$git_fetch_log" 2> "$git_fetch_err"; then
	echo "git fetch origin ${UNSHALLOW:+"$UNSHALLOW"} '$BEFORE:refs/private/before' '$AFTER:refs/private/after' -- failed:"
	cat "$git_fetch_err"
	cat "$git_fetch_log"
	if ! git fetch -f . "$BEFORE":refs/private/before "$AFTER:refs/private/after" > "$git_fetch_log" 2> "$git_fetch_err"; then
	echo "git fetch . '$BEFORE:refs/private/before' '$AFTER:refs/private/after' -- also failed:"
	cat "$git_fetch_err"
	cat "$git_fetch_log"
	fi
	fi

[jsoref]

I've made some changes:

check-spelling/unknown-words.sh

Lines 1987 to 2004 in a92b165

	get_before() {
	if [ -z "$BEFORE" ]; then
	COMPARE="$(jq -r '.compare // empty' "$GITHUB_EVENT_PATH" 2>/dev/null)"
	AFTER="$(jq -r '.pull_request.head.sha // .after // empty' "$GITHUB_EVENT_PATH")"
	AFTER="${AFTER:-$GITHUB_SHA}"
	if [ -n "$COMPARE" ]; then
	BEFORE="$(echo "$COMPARE" | perl -ne 'if (m{/compare/(.*)\.\.\.}) { print $1; } elsif (m{/commit/([0-9a-f]+)$}) { print "$1^"; };')"
	BEFORE="$(call_curl \
	"$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/commits/$BEFORE" | jq -r '.sha // empty')"
	elif [ -n "$GITHUB_BASE_REF" ]; then
	BEFORE="$GITHUB_BASE_REF"
	elif [ -n "$AFTER" ] && [ -n "$GITHUB_REF_NAME" ]; then
	BEFORE="$(git reflog --no-abbrev --decorate|grep -v "$AFTER" |grep "$GITHUB_REF_NAME" | head -1 | perl -pe 's/\s.*//')"
	else
	BEFORE="$(git rev-parse "$AFTER"~)"
	fi
	get_something origin "$BEFORE" before
	get_something origin "$AFTER" after

Can you try using @prerelease?