Use short SHA in multitenant PR names (#529)

<!-- The PR description should answer 2 (maybe 3) important questions:
-->

### What

Small quality of life change.

<!-- What is this PR trying to accomplish (and why, if it's not
obvious)? -->

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### How

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.github/workflows/update-multitenant-dep.yaml

@@ -35,6 +35,9 @@ jobs:
           # get newest commit to use
           LATEST_SHA="$(cd ndc-postgres && git rev-parse HEAD)"
 
+          # get short sha too for title
+          LATEST_SHORT_SHA="$(cd ndc-postgres && git rev-parse --short HEAD)"
+
           BRANCH_NAME="update-ndc-postgres-to-$LATEST_SHA"
           DEP_FILEPATH="Cargo.toml"
 
@@ -65,10 +68,10 @@ jobs:
           # create a pull-requests containing the updates.
           gh pr create \
             --body "Commit in ndc-postgres: https://github.com/hasura/ndc-postgres/commit/$LATEST_SHA" \
-            --title "dep update: update ndc-postgres to $LATEST_SHA" \
+            --title "dep update: update ndc-postgres to $LATEST_SHORT_SHA" \
             --head "$BRANCH_NAME" \
             --base "main" \
-            --reviewer "hasura/native-databases"
+            --reviewer "hasura/api-pg"
 
       # scream into Slack if something goes wrong
       - name: Report Status