Replace blocking fs.readFileSync with non blocking fs.readFile in checkForChanges.js

[danielcondemarin]

What did you implement:

Closes: N/A

This PR implements a TODO that was left in checkForChanges.js > checkIfDeploymentIsNecessary which makes reading the zipFiles asynchronously, therefore should make checkForChanges run a bit faster, specially considering there is already a costly blocking operation after the read to compute the checksum per zipFile.

How did you implement it:

Simply replaced blocking fs.readFileSync with non blocking fs.readFile.

How can we verify it:

N/A

Todos:

• Write tests
• Write documentation
• Fix linting errors
• Make sure code coverage hasn't dropped
• Provide verification config / commands / resources
• Enable "Allow edits from maintainers" for this PR
• Update the messages below

Is this ready for review?: YES
Is it a breaking change?: NO

[pmuens]

Thanks for fixing this @danielcondemarin 👍

Just tested it and it works fine --> LGTM