[Bug 1898073] Change creationDate in telemetry.crash to date-time format

[BenWu]

https://bugzilla.mozilla.org/show_bug.cgi?id=1898073

The java schema validator that we use in the decoder (and these tests) will automatically validate the date-time format. The python validator needs some tweaking but that's only used in this repo's tests AFAIK

Only crash creationDate changed to limit risk

Checklist for reviewer:

• Commits should reference a bug or github issue, if relevant (if a bug is referenced, the pull request should include the bug number in the title)
• If adding a new field, the field should have a description (see Bug 1652842 - Add a blocklist field so the environment schema works with pre- and post-bug-1647225 data #576 for an example)
• If coming from a fork, run integration tests: ./.github/push-to-trigger-integration <username>:<branchname>

For glean changes:

• Update templates/include/glean/CHANGELOG.md

For modifications to schemas in restricted namespaces (see CODEOWNERS):

• Follow the change control procedure

[akkomar]

This changed type of creation_date column in generated schema to TIMESTAMP and is causing schema generator failure:

[2024-06-07, 03:48:11 UTC] {pod_manager.py:466} INFO - [base] --- /app/validate_schema_evolution/9cab73ff29262e01908ecece70436964343b3f5e_base-revision/telemetry.crash.4.txt
[2024-06-07, 03:48:11 UTC] {pod_manager.py:466} INFO - [base] +++ /app/validate_schema_evolution/355db31e060bcfcdcb3e40970c7407b3e520f1c6_generated-schemas/telemetry.crash.4.txt
[2024-06-07, 03:48:11 UTC] {pod_manager.py:466} INFO - [base] @@ -11,3 +11,3 @@
[2024-06-07, 03:48:11 UTC] {pod_manager.py:466} INFO - [base] root.client_id STRING
[2024-06-07, 03:48:11 UTC] {pod_manager.py:466} INFO - [base] -root.creation_date STRING
[2024-06-07, 03:48:11 UTC] {pod_manager.py:466} INFO - [base] +root.creation_date TIMESTAMP
[2024-06-07, 03:48:11 UTC] {pod_manager.py:466} INFO - [base] root.document_id STRING