tests: remove test for strcasecmp

strcasecmp is a posix function, testing it doesn't make sense.
Functions that needs unsigned compare should use git__strcasecmp()

tests/clar/clar.c

@@ -41,9 +41,6 @@
 #	ifndef strdup
 #		define strdup(str) _strdup(str)
 #	endif
-#	ifndef strcasecmp
-#		define strcasecmp(a,b) _stricmp(a,b)
-#	endif
 
 #	ifndef __MINGW32__
 #		pragma comment(lib, "shell32")

tests/util/string.c

@@ -111,12 +111,6 @@ void test_string__strcasecmp(void)
 	cl_assert(git__strcasecmp("foo", "FOO") == 0);
 	cl_assert(git__strcasecmp("foo", "fOO") == 0);
 
-	cl_assert(strcasecmp("rt\303\202of", "rt dev\302\266h") > 0);
-	cl_assert(strcasecmp("e\342\202\254ghi=", "et") > 0);
-	cl_assert(strcasecmp("rt dev\302\266h", "rt\303\202of") < 0);
-	cl_assert(strcasecmp("et", "e\342\202\254ghi=") < 0);
-	cl_assert(strcasecmp("\303\215", "\303\255") < 0);
-
 	cl_assert(git__strcasecmp("rt\303\202of", "rt dev\302\266h") > 0);
 	cl_assert(git__strcasecmp("e\342\202\254ghi=", "et") > 0);
 	cl_assert(git__strcasecmp("rt dev\302\266h", "rt\303\202of") < 0);