Cirq v1.6.1 release

[Pavol Juhas]

Dear Cirq Users,

We have just released the patch-update of Cirq v1.6.1.
The release fixes a bug in  cirq.kraus  which in some cases
made it return erroneous near-zero matrices (#7536).
The release also includes minor documentation updates.

Please install or upgrade using

  pip install "cirq==1.6.1"

For further detail, please see release notes at
https://github.com/quantumlib/Cirq/releases/tag/v1.6.1.

Thank you,

Pavol