Add pooch cache manager verbosity control

[bjlittle]

🚀 Pull Request

Description

This pull-request adds explicit API level support to control the verbosity of the pooch cache manager within geovista.

Initially configured through the GEOVISTA_POOCH_MUTE environment variable (defaults to FALSE), thereafter through the geovista.cache.pooch_mute().

---

[codecov]

Codecov Report

Merging #482 (90b2e12) into main (ef9a0c9) will increase coverage by 0.05%.
Report is 1 commits behind head on main.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #482      +/-   ##
==========================================
+ Coverage   90.69%   90.74%   +0.05%     
==========================================
  Files          69       70       +1     
  Lines        3663     3684      +21     
==========================================
+ Hits         3322     3343      +21     
  Misses        341      341              

Files	Coverage Δ
src/geovista/cache.py	85.71% <100.00%> (+1.26%)	⬆️
tests/cache/test_pooch_mute.py	100.00% <100.00%> (ø)