feat: optional filtering on upstream HTTP headers (#121)

chore: upgrade dependencies

fix(notification): mask sensitive data in logs

fix: remove additionnal line break

close #107

fix: bufio.Scanner: token too long

close #98

refactor(config): small config refactoring

- split config structure
- improve config logic
- improve test lib and fix typos

v1.18.0

- Build static binary
- Add default extension parameter