add grep check

Author: sbryngelson

.github/workflows/lint-source.yml

@@ -33,3 +33,16 @@ jobs:
 
     - name: Ensure kind is specified
       run:  fortitude check --file-extensions=f90,fpp,fypp --select=P001 ./src/**
+
+  double-check:
+    name: Look for double intrinsics
+    runs-on: 'ubuntu-latest'
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Check for doubles via grep
+      run: |
+        cd src |
+        grep -iR 'dexp\|dlog\|dble\|dabs\|double\ precision\|real(8)\|real(4)\|dprod\|dmin\|dmax\|dfloat\|dreal\|dcos\|dsin\|dtan\|dsign\|dtanh\|dsinh\|dcosh\|\.d0\|\dd0' --exclude-dir=syscheck ./* || true |
+        grep -qiR 'dexp\|dlog\|dble\|dabs\|double\ precision\|real(8)\|real(4)\|dprod\|dmin\|dmax\|dfloat\|dreal\|dcos\|dsin\|dtan\|dsign\|dtanh\|dsinh\|dcosh\|\.d0\|\dd0' --exclude-dir=syscheck ./*