chore(testproxy): Remove multiple known failures that have already be…

…en addressed (#1560)

* Reduce list

* Remove another test that has been addressed

* We got another passing test for free

testproxy/known_failures.txt

@@ -2,8 +2,6 @@ TestMutateRow_Generic_DeadlineExceeded\|
 TestMutateRow_Generic_CloseClient\|
 TestMutateRows_Generic_CloseClient\|
 TestMutateRows_Retry_WithRoutingCookie\|
-TestReadModifyWriteRow_NoRetry_MultiValues\|
-TestReadModifyWriteRow_Generic_MultiStreams\|
 TestReadRow_Generic_DeadlineExceeded\|
 TestReadRow_Retry_WithRoutingCookie\|
 TestReadRow_Retry_WithRetryInfo\|
@@ -14,10 +12,8 @@ TestReadRows_Retry_WithRoutingCookie\|
 TestReadRows_Retry_WithRoutingCookie_MultipleErrorResponses\|
 TestReadRows_Retry_WithRetryInfo\|
 TestReadRows_Retry_WithRetryInfo_MultipleErrorResponse\|
-TestCheckAndMutateRow_Generic_DeadlineExceeded\|
 TestCheckAndMutateRow_NoRetry_TrueMutations\|
 TestCheckAndMutateRow_NoRetry_FalseMutations\|
-TestCheckAndMutateRow_Generic_MultiStreams\|
 TestSampleRowKeys_Generic_DeadlineExceeded\|
 TestSampleRowKeys_Retry_WithRoutingCookie\|
 TestSampleRowKeys_Generic_CloseClient