Update GitLab issues templates

Use the new links pointing to the GNOME Handbook website,
as the wiki has been decommissioned.

.gitlab/issue_templates/Bug.md

@@ -1,5 +1,5 @@
 <!-- 
-Please read https://wiki.gnome.org/Community/GettingInTouch/BugReportingGuidelines
+Please read https://handbook.gnome.org/issues/reporting.html
 first to ensure that you create a clear and specific issue.
 -->
 
@@ -46,7 +46,7 @@ screenshots or screencasts related, please provide them here.
 If the bug is a crash, please obtain a stack trace with installed debug
 symbols (at least for GNOME Calendar) and attach it to
 this issue following the instructions on
-https://wiki.gnome.org/Community/GettingInTouch/Bugzilla/GettingTraces.
+https://handbook.gnome.org/issues/stack-traces.html
 -->
 
 

.gitlab/issue_templates/Feature.md

@@ -1,5 +1,5 @@
 <!-- 
-Please read https://wiki.gnome.org/Community/GettingInTouch/BugReportingGuidelines
+Please read https://handbook.gnome.org/issues/reporting.html
 first to ensure that you create a clear and specific issue.
 -->