Update release checklist

Add two items to the release checklist to ensure that the start and the
end of the code freeze for each release cycle is announced on
Mattermost.

diff --git a/.gitlab/issue_templates/Release.md b/.gitlab/issue_templates/Release.md
index 53110fa41a83a180c912eafd920d5241e35d84e4..1e73f509a6e641b61720494a3a98b146d77a61e1 100644 (file)
--- a/.gitlab/issue_templates/Release.md
+++ b/.gitlab/issue_templates/Release.md
@@ -36,6 +36,7 @@
  - [ ] ***(QA)*** Check whether all issues assigned to the release milestone are resolved[^1].
  - [ ] ***(QA)*** Ensure that there are no outstanding merge requests in the private repository[^1] (Subscription Edition only).
  - [ ] ***(QA)*** Ensure all merge requests marked for backporting have been indeed backported.
+ - [ ] ***(QA)*** Announce (on Mattermost) that the code freeze is in effect.
 
 ### Before the Tagging Deadline
 
@@ -56,6 +57,7 @@
 ### Before the ASN Deadline (for ASN Releases) or the Public Release Date (for Regular Releases)
 
  - [ ] ***(QA)*** Verify GitLab CI results for the tags created and prepare a QA report for the releases to be published.
+ - [ ] ***(QA)*** Announce (on Mattermost) that the code freeze is over.
  - [ ] ***(QA)*** Request signatures for the tarballs, providing their location and checksums.
  - [ ] ***(Signers)*** Validate tarball checksums, sign tarballs, and upload signatures.
  - [ ] ***(QA)*** Verify tarball signatures and check tarball checksums again.