Allows passing of regex type (#832)

without this change if one does $(regex("[0-9]")) we have no knowledge of whether the result should be text or a number. What we do ATM is we always generate a String
with this change once can pass the type of regular expression and we will generate the concrete value of that given type

fixes gh-768

samples/standalone/dsl/http-client/src/test/java/com/example/loan/LoanApplicationServiceTests.java

@@ -74,7 +74,7 @@ public class LoanApplicationServiceTests {
 		// when:
 		int count = service.countAllFrauds();
 		// then:
-		assertThat(count).isEqualTo(200);
+		assertThat(count).isGreaterThanOrEqualTo(200);
 	}
 
 	@Test