adding anchor support to all headers

[parispittman]

Is your feature request related to a problem? Please describe

certain pages like community overview and contributing guide have anchors on the major headers but not the subheads (example: contributing code has an anchor link but not the contributor ladder underneath OR community overview and no anchor for core team)

Describe the solution you'd like

anchor links for all headers no matter the size; hover over

https://www.swift.org/community/#community-structure

https://www.swift.org/contributing/#contributing-code

[MahdiBM]

Looks like a duplicate of #831 🙂