Merge pull request #2203 from cgarciae:v0.5.2

PiperOrigin-RevId: 456237317

Merge pull request #2182 from yechengxi:patch-1

PiperOrigin-RevId: 454138229

Merge pull request #2134 from jheek:version-0.5.0

PiperOrigin-RevId: 450415939

Merge pull request #2103 from marcvanzee:v0_4_2

PiperOrigin-RevId: 446682006

Merge pull request #2098 from mattjj:avoid-units-axes-scan

PiperOrigin-RevId: 445929745

Merge pull request #2010 from andsteing:release

PiperOrigin-RevId: 436714568

Merge pull request #1825 from marcvanzee:pipy

PiperOrigin-RevId: 424597780

Merge pull request #1645 from google/newversion

Version 0.3.6

Merge pull request #1551 from jheek:version-0.3.5

PiperOrigin-RevId: 397933286

Merge pull request #1318 from google/new-version

New Flax release: v0.3.4