Use SDL_arraysize() - 1 to take length of INTERIM_COMMIT

Since INTERIM_COMMIT is a char array whose size we know for sure at
compile time, and which we also know is an array (instead of being a
pointer), we can take the SDL_arraysize() of it. However,
SDL_arraysize() doesn't account for the null terminator unlike
SDL_strlen(), so we'll have to do it ourselves. But at least we are
guaranteed to get a constant value at compile time, unlike if we use
SDL_strlen(), which would be repeatedly evaluating a constant value at
runtime.

To my knowledge, there's no equivalent SDL_arraysize() for constant
strings, and a quick `rg` (ripgrep) for "sizeof" in the SDL include/
folder doesn't show anything like that. So we'll just have to use the
SDL_arraysize() - 1 and deal with it.

desktop_version/src/Render.cpp

@@ -66,7 +66,7 @@ void menurender()
         graphics.Print( 310 - (10*8), 210, COMMIT_DATE, tr/2, tg/2, tb/2);
 #endif
 #ifdef INTERIM_COMMIT
-        graphics.Print( 310 - SDL_strlen(INTERIM_COMMIT) * 8, 220, INTERIM_COMMIT, tr/2, tg/2, tb/2);
+        graphics.Print( 310 - (SDL_arraysize(INTERIM_COMMIT) - 1) * 8, 220, INTERIM_COMMIT, tr/2, tg/2, tb/2);
 #endif
         graphics.Print( 310 - (4*8), 230, "v2.3", tr/2, tg/2, tb/2);