Update ghcr.io/osgeo/gdal Docker tag to ubuntu-small-3.8.5 (7.6-gdal3.8)

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
ghcr.io/osgeo/gdal	final	patch	ubuntu-small-3.8.0 -> ubuntu-small-3.8.5

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