Fix bug where Milestone page led to console error

Merged Kushal Pandya requested to merge 334468-add-time-tracker-null-check into master

What does this MR do?

Fixes a bug in time_tracker.vue where missing property led to console error and broken Time tracking component on Group Milestone.

Does this MR meet the acceptance criteria?

Conformity

Availability and Testing

Security

Does this MR contain changes to processing or storing of credentials or tokens, authorization and authentication methods or other items described in the security review guidelines? If not, then delete this Security section.

  • Label as security and @ mention @gitlab-com/gl-security/appsec
  • The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
  • Security reports checked/validated by a reviewer from the AppSec team

Related to #334468 (closed)

Edited by Kushal Pandya