Remove Unused Tests

[tomadamatkinson]

Description

Removes unused tests. These tests either do not currently work, do not get run in CI or test capabilities that the project does not support. Removing these tests simplifies the project further.

system_tests
Around from the early days. Are not super useful as they do not test actual framework usage. Are not run in CI and are not actively updated (other than compile errors). I believe these add no substantial value and we should encourage using Catch2 where necessary to test actual code.

generate project
This is used in the CI but we do not actively test Vulkan Samples as a dependency to another project. We also do not encourage users of the project to clone the framework.

generate sample
This test no longer works. It is also not used in the CI and currently new sample builds take up a lot of time! #458 might be able to fix this

Fixes #959

General Checklist:

Please ensure the following points are checked:

• My code follows the coding style
• I have reviewed file licenses
• I have commented any added functions (in line with Doxygen)
• I have commented any code that could be hard to understand
• My changes do not add any new compiler warnings
• My changes do not add any new validation layer errors or warnings
• I have used existing framework/helper functions where possible
• My changes do not add any regressions
• I have tested every sample to ensure everything runs correctly
• This PR describes the scope and expected impact of the changes I am making

Note: The Samples CI runs a number of checks including:

• I have updated the header Copyright to reflect the current year (CI build will fail if Copyright is out of date)
• My changes build on Windows, Linux, macOS and Android. Otherwise I have documented any exceptions

If this PR contains framework changes:

• I did a full batch run using the batch command line argument to make sure all samples still work properly

Sample Checklist

If your PR contains a new or modified sample, these further checks must be carried out in addition to the General Checklist:

• I have tested the sample on at least one compliant Vulkan implementation
• If the sample is vendor-specific, I have tagged it appropriately
• I have stated on what implementation the sample has been tested so that others can test on different implementations and platforms
• Any dependent assets have been merged and published in downstream modules
• For new samples, I have added a paragraph with a summary to the appropriate chapter in the readme of the folder that the sample belongs to e.g. api samples readme
• For new samples, I have added a tutorial README.md file to guide users through what they need to know to implement code using this feature. For example, see conditional_rendering
• For new samples, I have added a link to the Antora navigation so that the sample will be listed at the Vulkan documentation site

[SaschaWillems]

LGTM