Update dependencies, deprecations, and minor bug fixes

This is mostly a maintenance release that updates the underlying dependencies and addresses some deprecated features since the last release.

express-http-proxy is now targeting compatibility with node 16, 18, and 20.

v1.6.3

Allow author to delete headers in userResHeaderDecorator.

v1.6.2

Update node.js versions used in ci build.

v1.6.1

Small bug fixes and documentation enhancements.

Streaming by default, custom error handling

See release notes in project.

Add step for modifying user headers.

v1.1.0

Update README

Test and documentation updates.

Update dependencies. Improve docs on promise rejection. Fix promise rejection on body limit. Improve debug output.