Move overflow_underflow_toinf_0 from runtests to gtest

gtest is the preferred framework for simple tests that don't require
passing special command-line options to glslang.

gtests/AST.FromFile.cpp

@@ -301,6 +301,7 @@ INSTANTIATE_TEST_SUITE_P(
         "coord_conventions.frag",
         "gl_FragCoord.frag",
         "glsl.interpOp.error.frag",
+        "overflow_underflow_toinf_0.frag",
     })),
     FileNameAsCustomTestSuffix
 );