patch 9.1.0686: zip-plugin has problems with special characters

Problem:  zip-plugin has problems with special characters
          (user202729)
Solution: escape '*?[\' on Unix and handle those chars
          a bit differently on MS-Windows, add a test, check
          before overwriting files

runtime(zip): small fixes for zip plugin

This does the following:
- verify the unzip plugin is executable when loading the autoload plugin
- handle extracting file names with '[*?\' in its name correctly by
  escaping those characters for the unzip command (and handle those
  characters a bit differently on MS-Windows, since the quoting is different)
- verify, that the extract plugin is not overwriting a file (could cause
  a hang, because unzip asking for confirmation)
- add a test zip file which contains those special file names

fixes: #15505
closes: #15519

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/Filelist b/Filelist
index 9a0cf30..803de2a 100644
--- a/Filelist
+++ b/Filelist
@@ -221,6 +221,7 @@
 		src/testdir/samples/*.vim \
 		src/testdir/samples/test000 \
 		src/testdir/samples/test.zip \
+		src/testdir/samples/testa.zip \
 		src/testdir/color_ramp.vim \
 		src/testdir/silent.wav \
 		src/testdir/popupbounce.vim \