Post release 3.4.1 reset

[wpbonelli]

Reinitialize develop from master and reset version to 3.dev4 following release of 3.4.1

[codecov]

Codecov Report

Merging #1859 (7014486) into develop (5190394) will increase coverage by 0.0%.
The diff coverage is 80.0%.

@@           Coverage Diff           @@
##           develop   #1859   +/-   ##
=======================================
  Coverage     72.2%   72.3%           
=======================================
  Files          256     256           
  Lines        56120   56112    -8     
=======================================
+ Hits         40561   40575   +14     
+ Misses       15559   15537   -22     

Impacted Files	Coverage Δ
flopy/mf6/modflow/mfems.py	77.7% <ø> (ø)
flopy/mf6/modflow/mfgnc.py	92.0% <ø> (ø)
flopy/mf6/modflow/mfgwf.py	100.0% <ø> (ø)
flopy/mf6/modflow/mfgwfapi.py	100.0% <ø> (ø)
flopy/mf6/modflow/mfgwfbuy.py	100.0% <ø> (ø)
flopy/mf6/modflow/mfgwfchd.py	100.0% <ø> (ø)
flopy/mf6/modflow/mfgwfcsub.py	100.0% <ø> (ø)
flopy/mf6/modflow/mfgwfdis.py	100.0% <ø> (ø)
flopy/mf6/modflow/mfgwfdisu.py	100.0% <ø> (ø)
flopy/mf6/modflow/mfgwfdisv.py	100.0% <ø> (ø)
... and 62 more

... and 4 files with indirect coverage changes

[mwtoews]

Similar comment to MODFLOW-USGS/modflow6#1283 this should be 3.4.2.dev0.

Also, the post-release version from 3.4.0 would normally be 3.4.0.post0. But 3.4.1 is not a big deal. The difference between a micro increment vs post-release is not always obvious. (Often it's just a packaging difference). The micro increment was actually fine, since it includes a bug fix. Versions are cheap to make!