WinPTY-rs release v0.3.7

Minor winpty-rs release that brings compatibility with windows-rs version 0.38.0

What's Changed

• Bump codecov/codecov-action from 2 to 3 by @dependabot in #32
• Update windows requirement from 0.29.0 to 0.38.0 by @dependabot in #37

Full Changelog: v0.3.6...v0.3.7