Description
swagger validation broke due to automatic github upgrade to ubuntu 24.04
actions/runner-images#10636

Turns out github action has switched their repo and newer versions just work, so switched and pinned ubuntu version

Review Instructions
swagger/openapi validation job should just work in develop

Issue
n/a

Security and Privacy

None

Please make sure that you've checked the following before submitting your pull request. Thanks!

• Check that you pass the basic style checks and unit tests by running mvn clean install
• Ensure that the PR targets the correct branch. Check the milestone or fix version of the ticket.
• Follow the existing JPA patterns for queries, using named parameters, to avoid SQL injection
• If you are changing dependencies, check the Snyk status check or the dashboard to ensure you are not introducing new high/critical vulnerabilities
• Assume that inputs to the API can be malicious, and sanitize and/or check for Denial of Service type values, e.g., massive sizes
• Do not serve user-uploaded binary images through the Dockstore API
• Ensure that endpoints that only allow privileged access enforce that with the @RolesAllowed annotation
• Do not create cookies, although this may change in the future
• If this PR is for a user-facing feature, create and link a documentation ticket for this feature (usually in the same milestone as the linked issue). Style points if you create a documentation PR directly and link that instead.