Make pyresample dependency optional

[ghiggi]

Prework

• [x] I understand and agree to this repository's code of conduct.
• [x] I understand and agree to this repository's contributing guidelines.
• [x] I have already submitted an issue or discussion thread to discuss my idea with the maintainers.

What kind of change does this PR introduce? (check at least one)

• [ ] Bugfix
• [x] Feature
• [ ] Documentation
• [ ] Tutorial
• [ ] Code style update
• [x] Refactor
• [ ] Build-related changes
• [ ] Other, please describe:

Does this PR introduce a breaking change? (check one)

• [ ] Yes
• [x] No

If yes, please describe the impact and communicate accordingly:

The PR fulfills these requirements:

• [ ] It's submitted to the branch named as follow:
  • Fix a bug: bugfix-<some_key>-<word>
  • Improve the doc: doc-<some_key>-<word>
  • Improve a tutorial tutorial-<some_key>-<word>
  • Add a new feature: feature-<some_key>-<word>
  • Refactor some code: refactor-<some_key>-<word>
  • Optimize some code: optimize-<some_key>-<word>
• [ ] When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)
• [ ] Don't forget to link PR to issue if you are solving one.
• [x] All tests are passing.
• [ ] New/updated tests are included

Summary

Remove pyresample as mandatory dependency. This simplify GPM-API installation on Windows OS.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 33.80282% with 47 lines in your changes are missing coverage. Please review.

Project coverage is 87.66%. Comparing base (3df13b6) to head (050db43).

Files	Patch %	Lines
gpm/utils/pyresample.py	30.00%	28 Missing :warning:
gpm/dataset/crs.py	34.48%	19 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #50 +/- ## ========================================== + Coverage 87.56% 87.66% +0.09% ========================================== Files 110 111 +1 Lines 10501 10520 +19 ========================================== + Hits 9195 9222 +27 + Misses 1306 1298 -8 ```

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[coveralls]

coverage: 87.662% (+0.1%) from 87.563% when pulling 050db43d1a271299b948b662350b9e5a3f76fef9 on refactor-dependencies into 3df13b6b643daf532ce8ce5057432cb6d7a5ea41 on main.