[NEW] dynamically list test files

[dev-jonghoonpark]

The problem/use-case that the feature addresses

Currently the test_helper.tcl file maintains a list of test file names all_tests and iterates throught the list to execute all tests. the all_tests variable needs to be manually updated when new test files are introduced.

Description of the feature

dynamically list test files

Alternatives you've considered

Currently, the all_tests variable contains tests from four paths.

• unit
• unit/type
• unit/cluster
• integration

So, we'll implement files in these four paths to be dynamically added to the all_tests variable.

Additional information

I've already merged this feature into the valkey project, which is a fork of redis.
valkey-io/valkey#313

I would like to merge it into redis as well, if it is allowed.

[sundb]

@dev-jonghoonpark thanks, your contributions are welcome.