CI: Check DVC isexec metadata in "Style Checks" workflow (#4615)

* Add style check for DVC executable PNG metadata

* Remove executable metadata from baseline DVC files

Author: seisman

.github/workflows/style_checks.yaml

@@ -66,3 +66,14 @@ jobs:
             rm output.txt
             exit $nfiles
           fi
+
+      - name: Ensure baseline PNG DVC metadata does not mark files executable
+        run: |
+          grep -l '^[[:space:]]*isexec:[[:space:]]*true$' pygmt/tests/baseline/*.png.dvc > output.txt || true
+          nfiles=$(wc --lines output.txt | awk '{print $1}')
+          if [[ $nfiles > 0 ]]; then
+            echo "The following baseline PNG DVC files mark images as executable:"
+            cat output.txt
+            rm output.txt
+            exit $nfiles
+          fi

pygmt/tests/baseline/test_grdcontour_multiple_levels.png.dvc

@@ -1,6 +1,5 @@
 outs:
 - md5: 4d20cdb71af2e6568f64f0246ec860ea
   size: 64008
-  isexec: true
   hash: md5
   path: test_grdcontour_multiple_levels.png

pygmt/tests/baseline/test_grdcontour_one_level.png.dvc

@@ -1,6 +1,5 @@
 outs:
 - md5: fc624766f0b8eac8206735a05c7c9662
   size: 45023
-  isexec: true
   hash: md5
   path: test_grdcontour_one_level.png