create rulset file

Author: Malmahrouqi3

.github/workflows/ruleset.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ruleset name="Fortran Files in src Directory"
+         xmlns="http://pmd.sourceforge.net/ruleset/2.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://pmd.sourceforge.net/ruleset/2.0.0
+         http://pmd.sourceforge.net/ruleset_2_0_0.xsd">
+    <description>
+        Ruleset to analyze only Fortran files within the src directory.
+    </description>
+
+    <!-- Only run on Fortran files in src/ directory and Python files in toolchain/ directory -->
+    <filepattern><MFC/>src/.*\.(f|fpp|for|f90|f95|f03|f08)$</filepattern>
+    <filepattern><MFC/>toolchain/.*\.(py)$</filepattern>
+
+</ruleset>