Change timeouts to double for blocking list commands

[ibensw]

Since redis 6.0.0, blocking list commands accept doubles as timeouts instead of integers.

This pull request updates the following parameters for the commands blpop, brpop, brpoplpush and blmove:

• long long timeout to double timeout
• std::chrono::seconds to std::chrono::duration<double>

[sewenew]

Thanks for the contribution!

However, this PR has 2 problems:

• The test code fails to build, it seems that it's not compatible with existent code
• The change cannot work with Redis server older than 6.0

Looks like that we need to add an overloads instead of changing the type of timeout parameter from std::chrono::seconds to std::chrono::duration<double>.

Regards

[ibensw]

Thank you for your feedback.
Running the tests on redis server 7.0.15 does not yield any failures. What failures did you observe?
Your comment for older redis versions stands. I will change add the overloads instead of changing them.

[sewenew]

My bad! Looks like my building env is problematic, and it failed to build the test code. I cleaned the building env, and rebuild the code, it can build successfully, although the test fails with redis 4.0.

Regards