patch 8.2.1970: it is easy to make mistakes when cleaning up swap files

Problem:    It is easy to make mistakes when cleaning up swap files after the
            system crashed.
Solution:   Warn for the process still running after recovery.  Do not
            automatically delete a swap file created on another system.
            (David Fries, closes #7273)
diff --git a/src/version.c b/src/version.c
index f452d96..8cf37f0 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1970,
+/**/
     1969,
 /**/
     1968,