v1.5.1 Release

What's Changed

• test: add some unit tests for settings by @cameri in #12
• add settings unit tests by @cameri in #14
• test: delegated event message handler by @cameri in #16
• Add PR template & contributing doc by @cameri in #15
• test: add unit tests for SubscribeMessageHandler by @cameri in #17
• doc: add CONFIGURATION.md by @cameri in #20
• Add integration tests for NIP-1 by @cameri in #18

Full Changelog: https://github.com/Cameri/nostr-ts-relay/commits/v1.5.1