update nghttp2 to v1.45.1

[targos]

https://github.com/nghttp2/nghttp2/releases/tag/v1.45.1

We are currently at v1.42.0.

@nodejs/http2

[mcollina]

cc @jasnell

[targos]

v1.45.0 was released today

[thunder-coding]

According to https://github.com/nodejs/node/blob/master/doc/guides/contributing/pull-requests.md#dependencies, PRs for dependencies won't be accepted but this issue seems to have a help wanted label. So, will my PR be accepted if I fix this?

[mcollina]

Version updates are just about the only thing accepted, send it over!

[gengjiawen]

#40206 landed.