MacOS gmock build fix

Updated gmock complains about missing regex_t. This is likely a macos
configuration issue and needs to be fixed, but fot now just forcing the
declaration

indra/test/test.cpp

@@ -54,6 +54,12 @@
 #endif
 
 #ifndef LL_WINDOWS
+
+typedef struct {
+  void *re_pcre;
+  size_t re_nsub;
+  size_t re_erroffset;
+} regex_t;
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 #endif