ci: set --pr-id flag

.ci/deploy/pantheon/dev-multidev

@@ -14,10 +14,15 @@ terminus build:gitignore:cut
 # Authenticate with Terminus
 terminus -n auth:login --machine-token="$TERMINUS_TOKEN"
 
-if [[ $CI_BRANCH != $DEFAULT_BRANCH ]]
+if [[ "$CI_BRANCH" != "$DEFAULT_BRANCH" ]]
 then
-  # Create a new multidev environment (or push to an existing one)
-  terminus -n build:env:create "$TERMINUS_SITE.dev" "$TERMINUS_ENV" --yes
+  if [ -n "$PR_NUMBER" ]; then
+    # Create a new multidev environment (or push to an existing one) with PR id set
+    terminus -n build:env:create "$TERMINUS_SITE.dev" "$TERMINUS_ENV" --yes --pr-id="$PR_NUMBER"
+  else
+    # Create a new multidev environment (or push to an existing one)
+    terminus -n build:env:create "$TERMINUS_SITE.dev" "$TERMINUS_ENV" --yes
+  fi
 else
   # Push to the dev environment
   terminus -n build:env:push "$TERMINUS_SITE.dev" --yes
@@ -37,10 +42,10 @@ fi
 terminus -n drush "$TERMINUS_SITE.$TERMINUS_ENV" -- cr
 
 # Clear the environment cache
-terminus -n env:clear-cache $TERMINUS_SITE.$TERMINUS_ENV
+terminus -n env:clear-cache "$TERMINUS_SITE"."$TERMINUS_ENV"
 
 # Ensure secrets are set
 terminus -n secrets:set "$TERMINUS_SITE.$TERMINUS_ENV" token "${GH_TOKEN:-$GITHUB_TOKEN}" --file='.build-secrets/tokens.json' --clear --skip-if-empty
 # Delete old multidev environments associated
 # with a PR that has been merged or closed.
-terminus -n build:env:delete:pr $TERMINUS_SITE --yes
+terminus -n build:env:delete:pr "$TERMINUS_SITE" --yes