Change version of libprotobuf_mutator to equal the regular Atheris ve…

…rsion

Atheris version 2.3.0

Atheris version 2.2.2

Atheris version 2.1.1

Increase Atheris minor release number.

PiperOrigin-RevId: 462405790
Change-Id: Ie22e1475ec679d59dbc3c19faed16e7b38190d0a

Atheris version 2.0.11

Atheris version 2.0.10

Atheris version 2.0.9

Atheris version 2.0.8

Atheris version 2.0.6