bug#54281: 29.0.50; project-try-vc not return the root

[Shuguang Sun via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Hi all,

The `project-current' and `project-try-vc' can't return the root but
just a list of `(vc Git)'. It is found that an `and' should be used in
the function `project-try-vc' instead of `or'.

The patch below fixs it.

```
diff --git a/lisp/progmodes/project.el b/lisp/progmodes/project.el
index daaf86f327..e8bd203979 100644
--- a/lisp/progmodes/project.el
+++ b/lisp/progmodes/project.el
@@ -418,7 +418,7 @@ project-vc-external-roots-function
 backend implementation of `project-external-roots'.")
 
 (defun project-try-vc (dir)
-  (or (vc-file-getprop dir 'project-vc)
+  (and (vc-file-getprop dir 'project-vc)
       (let* ((backend (ignore-errors (vc-responsible-backend dir)))
              (root
               (pcase backend
```

Best Regards,
Shuguang Sun



In GNU Emacs 29.0.50 (build 1, x86_64-w64-mingw32)
 of 2022-03-07 built on 
Repository revision: 36b31d38cd9bde7ad1ec18c136854cddba0d6bbe
Repository branch: master
Windowing system distributor 'Microsoft Corp.', version 10.0.19044
System Description: Microsoft Windows 10 Pro (v10.0.2009.19044.1526)

Configured using:
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