v1.6.2

Speed up for the covariance computation using Adrien's trick of block diagonal matrix multiplication

What's Changed

• Feature namaster tests by @xgarrido in #54
• Bump pypa/cibuildwheel from 2.12.3 to 2.13.0 by @dependabot in #55
• Fix old and undefined method by @xgarrido in #56
• Adrien's idea by @thibautlouis in #57
• bump version 1.6.1->1.6.2 by @thibautlouis in #58

Full Changelog: v1.6.1...v1.6.2