patch 9.1.0474: CI: Test_ColonEight() fails on github runners

Problem:  CI: Test_ColonEight() fails on github runners
          (Ken Takata)
Solution: Run the test for files on the C: drive, where dos shortnames
          are still enabled, refactor the tests to use a single setup
          function for the preparation

fixes: #14954
closes: #14958

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index 78668ea..fc4490d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    474,
+/**/
     473,
 /**/
     472,