About.jl causes docs failure

[juliasloan25]

Describe the bug

The docs environment has About.jl as a dependency because it's used in an example in getting_started.md here. This package started producing an error in precompilation (see this link).

Since this package is only referenced in an .md file, not any .jl files, the Julia code snippet importing it isn't actually run during our docs build and I don't think we need to include it in our environment. Any users that want to run that code snippet can just add it for themselves.

The repo already has an issue open about this: tecosaur/About.jl#42

[juliasloan25]

cc @AlexisRenchon

[tecosaur]

FYI, I'm hoping to fix this shortly, but I'm chronically short on time and so can't make any guarantees.