Enable production vault cookers to use swh.graph

Related to T3518

Test Plan

octo-diff:

Expectedly, for production workers, the configuration is updated with the graph configuration key and the dependency python3-swh.graph.client is installed. For staging workers, nothing changes as there is no graph instance there.

$ bin/octocatalog-diff --octocatalog-diff-args --no-truncate-details --to staging worker12.euwest.azure
Found host worker12.euwest.azure.internal.softwareheritage.org
...
*******************************************
  File[/etc/softwareheritage/vault_cooker.yml] =>
   parameters =>
     content =>
      @@ -17,3 +17,5 @@
         - swh.vault.cooking_tasks.SWHBatchCookingTask
       max_bundle_size: 1073741824
      +graph:
      +  url: http://graph.internal.softwareheritage.org:5009/
      _
*******************************************
+ Package[python3-swh.graph.client] =>
   parameters =>
      "ensure": "present"
*******************************************
*** End octocatalog-diff on worker12.euwest.azure.internal.softwareheritage.org

$bin/octocatalog-diff --octocatalog-diff-args --no-truncate-details --to staging worker0.internal.staging.swh.network
Found host worker0.internal.staging.swh.network
...
*** Running octocatalog-diff on host worker0.internal.staging.swh.network
I, [2021-09-01T17:19:32.856260 #26813]  INFO -- : Catalogs compiled for worker0.internal.staging.swh.network
I, [2021-09-01T17:19:34.031670 #26813]  INFO -- : Diffs computed for worker0.internal.staging.swh.network
I, [2021-09-01T17:19:34.031705 #26813]  INFO -- : No differences
*** End octocatalog-diff on worker0.internal.staging.swh.network

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Migrated from D6169 (view on Phabricator)