Enhance cluster configuration with reconnection policy and improve code

[itsfuad]

This pull request includes changes to improve the resilience and robustness of the gocqlx library by adding reconnection policies and handling nil contexts. The most important changes include the addition of a constant reconnection policy in the CreateCluster function and the handling of nil contexts in the WithContext method.

Improvements to resilience and robustness:

• gocqlxtest/gocqlxtest.go: Added a constant reconnection policy to handle reconnections with a maximum of 10 retries and a 3-second interval between retries in the CreateCluster function.
• queryx_wrap.go: Modified the WithContext method in the Queryx struct to handle nil contexts by defaulting to context.Background().

[sylwiaszunejko]

Could you please squash your commits so that the commit history doesn't include 'fixes' commits? This will help keep the history cleaner and more concise. Thanks!

[itsfuad]

Yeah sure

[itsfuad]

Is that okay now?

[sylwiaszunejko]

I don't think the information about removing commented-out things and fixing formatting is necessary

[itsfuad]

Aw.. sorry for that. Can you please check now?

[dkropachev]

@itsfuad , thanks a lot for you contribution.