Add Roave BC check configuration with baseline for cast property type change

Author: zero-to-prod

.roave-backward-compatibility-check.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<roave-bc-check>
+    <baseline>
+        <ignored-regex>#\[BC\] CHANGED: Type of property Zerotoprod\\DataModel\\Describe\#\$cast changed from string\|array to string\|array\|Closure#</ignored-regex>
+    </baseline>
+</roave-bc-check>