v3.1.5

Changelog

• 9c642f8 Unblock reads when conn is closed
• e2959fd Remove the obsolete Go 1.14 build tag
• 8674b27 Update actions/checkout action to v7
• 8f512dc Update module github.com/pion/transport/v4 to v4.0.2 (#836)
• 1ce56ab Update dtls-1.2 branch name
• bc02e81 Document main-branch tagging freeze