KRaft support in OffsetFetchRequestTest

The following tests in OffsetFetchRequestTest in core/src/test/scala/unit/kafka/server/OffsetFetchRequestTest.scala need to be updated to support KRaft

83 : def testOffsetFetchRequestSingleGroup(): Unit = {

130 : def testOffsetFetchRequestAllOffsetsSingleGroup(): Unit = {

180 : def testOffsetFetchRequestWithMultipleGroups(): Unit = {

Scanned 246 lines. Found 0 KRaft tests out of 3 tests