test/catch2: remove completely

The catch2 subproject was removed and all users of it appear gone,
so remove this non-built cpp part as well.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I80c6db3ac4d0c4074a1fc708db9096445227bb31
diff --git a/test/catch2_main.cpp b/test/catch2_main.cpp
deleted file mode 100644
index 4ed06df..0000000
--- a/test/catch2_main.cpp
+++ /dev/null
@@ -1,2 +0,0 @@
-#define CATCH_CONFIG_MAIN
-#include <catch2/catch.hpp>