feat: support passing license as file

What's changed and what's your intention?

PLEASE DO NOT LEAVE THIS EMPTY !!!

Please explain IN DETAIL what the changes are in this PR and why they are needed:

[!NOTE] The environment variable used to pass the file path is RW_LICENSE_KEY_PATH due to a mistake in the original PR. We'll keep using it instead of changing it.

Support passing license keys via mounted secret file, which enables automatic license updating. Upstream PR: https://github.com/risingwavelabs/risingwave/pull/18768
Support version based auto detection and enablement of the feature and the ability of manual overriding.
The PR maintains backward compatibility at the API level.

Checklist

[x] I have written the necessary docs and comments
[x] I have added necessary unit tests and integration tests

Refer to a related PR or issue link (optional)

Codecov Report

Attention: Patch coverage is 90.90909% with 9 lines in your changes missing coverage. Please review.

Project coverage is 55.43%. Comparing base (c76f925) to head (0d8c9c2). Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
apis/risingwave/v1alpha1/zz_generated.deepcopy.go	0.00%	6 Missing :warning:
pkg/factory/risingwave_object_factory.go	96.77%	2 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #732 +/- ## ========================================== + Coverage 55.03% 55.43% +0.40% ========================================== Files 40 40 Lines 6679 6757 +78 ========================================== + Hits 3676 3746 +70 - Misses 2877 2884 +7 - Partials 126 127 +1 ``` | [Flag](https://app.codecov.io/gh/risingwavelabs/risingwave-operator/pull/732/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=risingwavelabs) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/risingwavelabs/risingwave-operator/pull/732/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=risingwavelabs) | `55.43% <90.90%> (+0.40%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=risingwavelabs#carryforward-flags-in-the-pull-request-comment) to find out more.

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risingwavelabs / risingwave-operator