Gdal version issue solved

[ruchimotwaniBC]

[Description of PR] Solves #869, the issue of gdal version.

Checklist:

• [x] Changes documented in CHANGES.md
• [x] GitHub CI passes
• [x] AppVeyor CI passes
• [x] Test coverage remains or increases (target 100%)

[codecov[bot]]

Codecov Report

All modified lines are covered by tests :white_check_mark:

Comparison is base (c1e0b76) 93.30% compared to head (0f33596) 93.30%. Report is 1 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #896 +/- ## ======================================= Coverage 93.30% 93.30% ======================================= Files 447 447 Lines 34833 34843 +10 ======================================= + Hits 32500 32510 +10 Misses 2333 2333 ``` | [Files](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop) | Coverage Δ | | |---|---|---| | [test/core/mldataset/test\_base.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-dGVzdC9jb3JlL21sZGF0YXNldC90ZXN0X2Jhc2UucHk=) | `100.00% <100.00%> (ø)` | | | [test/core/store/fs/test\_registry.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-dGVzdC9jb3JlL3N0b3JlL2ZzL3Rlc3RfcmVnaXN0cnkucHk=) | `98.09% <100.00%> (+<0.01%)` | :arrow_up: | | [test/core/test\_normalize.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-dGVzdC9jb3JlL3Rlc3Rfbm9ybWFsaXplLnB5) | `100.00% <100.00%> (ø)` | | | [test/core/test\_subsampling.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-dGVzdC9jb3JlL3Rlc3Rfc3Vic2FtcGxpbmcucHk=) | `100.00% <100.00%> (ø)` | | | [test/core/test\_tilingscheme.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-dGVzdC9jb3JlL3Rlc3RfdGlsaW5nc2NoZW1lLnB5) | `100.00% <100.00%> (ø)` | | | [test/webapi/ows/coverages/test\_controllers.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-dGVzdC93ZWJhcGkvb3dzL2NvdmVyYWdlcy90ZXN0X2NvbnRyb2xsZXJzLnB5) | `100.00% <100.00%> (ø)` | | | [test/webapi/tiles/test\_controllers.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-dGVzdC93ZWJhcGkvdGlsZXMvdGVzdF9jb250cm9sbGVycy5weQ==) | `100.00% <100.00%> (ø)` | | | [xcube/constants.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-eGN1YmUvY29uc3RhbnRzLnB5) | `100.00% <100.00%> (ø)` | | | [xcube/core/gridmapping/base.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-eGN1YmUvY29yZS9ncmlkbWFwcGluZy9iYXNlLnB5) | `96.33% <100.00%> (ø)` | | | [xcube/core/tilingscheme.py](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop#diff-eGN1YmUvY29yZS90aWxpbmdzY2hlbWUucHk=) | `97.44% <100.00%> (ø)` | | | ... and [3 more](https://app.codecov.io/gh/dcs4cop/xcube/pull/896?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dcs4cop) | |

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[pont-us]

More of a comment than a full review: We have a module constants.py. It would be best to declare the CRS85 string there once and then have every place that requires it import it. If there ever would be another change, we would then just have to change the one place.

In principle I agree that this would have been preferable, but I don't think that it's worth the additional effort to optimize it now. This PR already introduces module-level constants, which is at least a start. In the unlikely event that the identifier changes again, we can optimize to a global constant at that point.