Write Unittests for `lib/widgets/event_card.dart`

[palisadoes]

We will need unittests done for all methods, classes and functions found in this file.

Any widgets referenced in this file must also have unittests done

PR Acceptance Criteria

1. When complete this file must show 100% coverage when merged into the code base.
2. The current code coverage for the file can be found here
3. CodeRabbit must approve all your changes to the test file(s) and the file(s) under test
4. The PR will show a report for the code coverage for the file you have added. You can use that as a guide
5. No functionality must be removed to achieve this goal
6. All tests must be valid and truly test the code base

Potential internship candidates

Please read this if you are planning to apply for a Palisadoes Foundation internship

• https://github.com/PalisadoesFoundation/talawa/issues/359

[Rahul93102]

please, assign this issue to me.

[github-actions[bot]]

This issue did not get any activity in the past 10 days and will be closed in 180 days if no update occurs. Please check if the develop branch has fixed it and report again or close the issue.

[Cioppolo14]

@Rahul93102 Are you working on this?