fix(ci): better handling of merges in percy-skip-deps.sh

scripts/percy-skip-deps.sh

@@ -3,9 +3,16 @@
 set -o errexit
 set -o pipefail
 
-env | grep TRAVIS | sort
 
-git log --no-merges --name-only --pretty=format: ${1}..${2} | grep -Ev '^$' | sort | uniq | while read FILE ; do
+if [ "${TRAVIS_BRANCH}" == "master" ] && [ -n ${TRAVIS_COMMIT_RANGE} ]; then
+  RANGE="${TRAVIS_COMMIT_RANGE}"
+else
+  git fetch origin master
+  RANGE="FETCH_HEAD...${TRAVIS_COMMIT}"
+fi
+
+
+git log --no-merges --name-only --pretty=format: ${RANGE} | grep -Ev '^$' | sort | uniq | while read FILE ; do
   if [[ "${FILE}" =~ ^ui/src/.+ ]]; then
     echo "[P] ${FILE}"
     exit 1