Add srtm_bigtujunga30m_utm11 data and updated Roxygen2

[ktlenz]

This pull request adds the 30 m SRTM elevation data of the Big Tujunga catchment, including documentation and tests.

New dataset:

• Added srtm_bigtujunga30m_utm11 in inst/extdata and data, which provides the SRTM elevation data TIFF as a path for the Big Tujunga catchment.
• Added corresponding documentation for srtm_bigtujunga30m_utm11 in R/data.R using `Roxygen2 .

Testing:

• Added a test in tests/testthat/test-data.R to verify that the dataset loads correctly, the file exists, and can be used to create a GRIDobj.

Metadata update:

• Updated the RoxygenNote version in DESCRIPTION to 7.3.3.

[ktlenz]

@wkearn I do not quite get why the macos check is failing, would you mind having a look?

[wkearn]

I reran the tests for your most recent pull request, and they fail now (https://github.com/TopoToolbox/topotoolboxr/actions/runs/19281458575/job/56901339783), though they passed originally.

This is almost certainly something that has changed with terra between versions 1.8.80, which the previous tests used earlier, and 1.8.86, which the tests are now using. I think we may need to explicitly install GDAL and PROJ on macos. I'll mess around with the CI configuration and see if that fixes things.

[wkearn]

#57 should fix the errors here. Merge/rebase the main branch into your feature branch and see if the tests work.