[Cases] Guardrails: Total number cases update

[adcoelho]

Connected to #146945

Summary

Description	Limit	Done?	Documented?
Total number of cases to be updated	100	✅	Yes

• Also changed the minimum of cases that can be updated to 1.
• Tests.
• Updated Documentation.

Checklist

Delete any items that are not applicable to this PR.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios

Release Notes

The maximum number of cases that can be updated simultaneously is now 100. The minimum is 1.

[elasticmachine]

Pinging @elastic/response-ops (Team:ResponseOps)

[elasticmachine]

Pinging @elastic/response-ops-cases (Feature:Cases)

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: e2977b1

Metrics [docs]

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
cases	146.0KB	146.1KB	+78.0B

Unknown metric groups

ESLint disabled line counts

id	before	after	diff
enterpriseSearch	14	16	+2
securitySolution	410	414	+4
total			+6

Total ESLint disabled count

id	before	after	diff
enterpriseSearch	15	17	+2
securitySolution	489	493	+4
total			+6

History

• 💚 Build #139953 succeeded b0472c2
• 💚 Build #139745 succeeded 3fca220

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @adcoelho

[lcawl]

OAS LGTM, thanks!