[Backend] Reorganize version 1.0 codegen tests

- Extract all backend codegen tests that specifically target behaviour
  in to-be-deprecated functionality from language versions < 1.3"
- Remove those tests from the JVM IR test suite.

compiler/testData/codegen/box/operatorConventions/oldLanguageVersions/percentAsModOnBigIntegerWithoutRem.kt

@@ -0,0 +1,11 @@
+// !LANGUAGE: -ProhibitOperatorMod
+// !API_VERSION: 1.0
+// TARGET_BACKEND: JVM
+// FULL_JDK
+
+import java.math.BigInteger
+
+fun box(): String {
+    val m = BigInteger.valueOf(-2) % BigInteger.valueOf(3)
+    return if (m != BigInteger.valueOf(1)) "Fail: BigInteger(-2) mod BigInteger(3) == $m" else "OK"
+}