[CI] Fix release notification message, and add rustc version to release notes (#1191)

* Release announcements: s/kusama/polkadot/

* Additional debug info for gitlab publish script

* add rustc version check job

* fully comment out tag-checking

* s/podman/docker/g

* Switch to rust-builder image and install jq

* remove temporary TODOs

polkadot/scripts/gitlab/lib.sh

@@ -22,8 +22,10 @@ check_tag () {
   repo=$1
   tagver=$2
   if [ -n "$GITHUB_RELEASE_TOKEN" ]; then
+    echo '[+] Fetching tag using privileged token'
     tag_out=$(curl -H "Authorization: token $GITHUB_RELEASE_TOKEN" -s "$api_base/$repo/git/refs/tags/$tagver")
   else
+    echo '[+] Fetching tag using unprivileged token'
     tag_out=$(curl -H "Authorization: token $GITHUB_PR_TOKEN" -s "$api_base/$repo/git/refs/tags/$tagver")
   fi
   tag_sha=$(echo "$tag_out" | jq -r .object.sha)
@@ -31,6 +33,7 @@ check_tag () {
   if [ "$tag_sha" = "null" ]; then
     return 2
   fi
+  echo "[+] Tag object SHA: $tag_sha"
   verified_str=$(curl -H "Authorization: token $GITHUB_RELEASE_TOKEN" -s "$object_url" | jq -r .verification.verified)
   if [ "$verified_str" = "true" ]; then
     # Verified, everything is good

polkadot/scripts/gitlab/publish_draft_release.sh

@@ -24,9 +24,13 @@ case $? in
     ;;
   1) echo '[!] Tag found but has not been signed. Aborting release.'; exit 1
     ;;
-  2) echo '[!] Tag not found. Aborting release.'; exit
+  2) echo '[!] Tag not found. Aborting release.'; exit 1
 esac
 
+# Pull rustc version used by rust-builder for stable and nightly
+stable_rustc="$(rustc +stable --version)"
+nightly_rustc="$(rustc +nightly --version)"
+
 # Start with referencing current native runtime
 # and find any referenced PRs since last release
 # Note: Drop any changes that begin with '[contracts]' or 'contracts:'
@@ -41,6 +45,10 @@ release_text="Polkadot native runtime: $polkadot_spec
 Kusama native runtime: $kusama_spec
 
 Westend native runtime: $westend_spec
+
+This release was built with the following versions of \`rustc\`. Other versions may work.
+- $stable_rustc
+- $nightly_rustc
 "
 
 runtime_changes=""