Create test script to verify that the Linux tv-casting-app is able to discover the Linux tv-app.

[shaoltan-amazon]

As noted in #32787, there is currently no CI check in place to verify that the Linux tv-casting-app continues to work with the Linux tv-app whenever a PR is created and eventually merged in. This can result in the existing Matter casting experience breaking without knowing.

This issue will cover the initial creation of the test script along with the implementation logic for testing the discovery between the Linux tv-casting-app and the Linux tv-app. The idea is to run the Linux tv-casting-app and the Linux tv-app as separate processes, write their respective output to separate files, iterate through the tv-casting-app logs to find strings of interest to determine if the discovery was successful or not. Lastly, the command to run the test script for testing the discovery between the tv-casting-app and the tv-app will also be added to the workflow yaml file.

In the case of a successful discovery, we will print the following to console:

• For each commissioner that we discover, we will print the discovered commissioner number, their corresponding Vendor ID, Product ID, and Device Type. Furthermore, each commissioner along with their information will be stored in a list.
• Print the number of commissioner(s) that was discovered.
• Print 'Discovery success!'

In the case of a failed discovery, we will print the following to console:

• If we find the string "No commissioner discovered" in the Linux tv-casting-app log file, then print this line along with 'Discovery failed!', dump the logs to console, and exit on error.
• In the rare instance where we don't find the aforementioned string "No commissioner discovered" and there is no entry for "Discovered Commissioner" (meaning the list of discovered commissioner(s) is empty), then something went wrong while running the Linux tv-casting-app and/or Linux tv-app. Print 'Discovery failed!', dump the logs to console, and exit on error.
  Note: In either case of a failed discovery, the user should attempt to re-run the workflow and see if that allows for a successful discovery. If that does not pass, then the user should check their code to see how it is breaking the discovery process.

The next step is to test for the commissioning between the Linux tv-casting-app and the Linux tv-app. This will be created as a separate issue to be worked on.