Use double quotes in git shell command on Windows

Partially reverts commit f52a115ea9

Fixes #2003

Needs tests to prevent a future regression.

src/rebar_git_resource.erl

@@ -36,8 +36,8 @@ lock_(AppDir, {git, Url}) ->
     {ok, VsnString} =
         case os:type() of
             {win32, _} ->
-                rebar_utils:sh("git --git-dir=';" ++ Dir ++ "/.git' "
-                               "--work-tree=';" ++ Dir ++ "' rev-parse --verify HEAD",
+                rebar_utils:sh("git --git-dir=\";" ++ Dir ++ "/.git\" "
+                               "--work-tree=\";" ++ Dir ++ "\" rev-parse --verify HEAD",
                     [{use_stdout, false}, {debug_abort_on_error, AbortMsg}]);
             _ ->
                 rebar_utils:sh("git --git-dir='" ++ Dir ++ "/.git' rev-parse --verify HEAD",