[cleanup] Rm blank line (#37988)

Followup on https://github.com/grpc/grpc/pull/37983

Closes #37988

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/37988 from drfloob:winguh ba5fa0b296
PiperOrigin-RevId: 689137714

test/core/end2end/end2end_tests.cc

@@ -56,7 +56,6 @@ Slice RandomBinarySlice(size_t length) {
   std::vector<uint8_t> output;
   output.resize(length);
   for (i = 0; i < length; ++i) {
-
     output[i] = rand();
   }
   return Slice::FromCopiedBuffer(output);