[K/N] Commonize String.regionMatches function

As a part of efforts to stabilize K/N stdlib.

libraries/stdlib/common/src/kotlin/TextH.kt

@@ -311,6 +311,22 @@ expect fun CharSequence.regionMatches(
     ignoreCase: Boolean = false
 ): Boolean
 
+/**
+ * Returns `true` if the specified range in this string is equal to the specified range in another string.
+ * @param thisOffset the start offset in this string of the substring to compare.
+ * @param other the string against a substring of which the comparison is performed.
+ * @param otherOffset the start offset in the other string of the substring to compare.
+ * @param length the length of the substring to compare.
+ */
+@SinceKotlin("1.9")
+public expect fun String.regionMatches(
+    thisOffset: Int,
+    other: String,
+    otherOffset: Int,
+    length: Int,
+    ignoreCase: Boolean = false
+): Boolean
+
 
 /**
  * A Comparator that orders strings ignoring character case.