Do not display the `View Raw Logs` button when the error file is not available

[chandrashekar-s]

Description of what I changed

Fixes #745 Changes made to ensure the View Raw Logs is made available only when the log files are present.

E2E test

NA

TESTED:

Tested the existence of the button.

Checklist: I completed these to help reviewers :)

• [x] I have read and will follow the review process.

• [x] I am familiar with Google Style Guides for the language I have coded in.

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• [ ] I have added tests to cover my changes. (If you refactored existing code that was well tested you do not have to add tests)

• [x] I ran mvn clean package right before creating this pull request and added all formatting changes to my commit.

• [x] All new and existing tests passed.

• [x] My pull request is based on the latest changes of the master branch.

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