🐛 [firestore-bigquery-export] Cannot install a new instance after deleting the default service account more than 30 days ago.

### [READ] Step 1: Are you in the right place?

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If you have a general question, need help debugging, or fall into some
other category use one of these other channels:

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### [REQUIRED] Step 2: Describe your configuration

- Extension name: **firestore-bigquery-export** (`storage-resize-images`, `firestore-send-email`, etc)
- Extension version: **0.2.0**
- Configuration values (redact info where appropriate):
- omited

### [REQUIRED] Step 3: Describe the problem

#### Steps to reproduce:
1. Delete the default service account.
2. Try to install the extention.

##### Expected result
The installation succeeds.

##### Actual result
```
; RESOURCE_ERROR at /deployments/firebase-ext-firestore-bigquery-export-tife/resources/fsexportbigquery: {"ResourceType":"gcp-types/cloudfunctions-v2beta:projects.locations.functions","ResourceErrorCode":"404","ResourceErrorMessage":{"code":404,"message":"Service account projects/-/serviceAccounts/(redacted)-compute@developer.gserviceaccount.com was not found.","status":"NOT_FOUND","statusMessage":"Not Found","requestPath":"https://cloudfunctions.googleapis.com/v2beta/projects/(redacted)/locations/us-central1/functions","httpMethod":"POST"}}
```
I suspect that, during the installation process, a GCE instance tries to create a Cloud Function instance with the default service account, such as `***-compute@developer.gserviceaccount.com`. If you happen to have removed the default account more than 30 days ago, however, you have no means to install the extension any more because you cannot restore the account nor can you choose which service account to use for the installation.