Warehouse: Copyable 'pip install <foo>' line should likely quote <foo> in some cases

[Julian]

Describe the bug
PyPI shows a copyable pip install <foo> command line, and includes the version when visiting a particular release. (Though there's some discussion in #1563 and #3006 about improving or dropping it).

For a release containing a PEP 440 Epoch, Warehouse shows:

The line there is likely not something someone wants to copy paste.

In various shells (zsh, bash) the ! there will trigger history completion or the like (so 3!2 will complete in the history line number 2 in the shell history file).

Expected behavior
<foo> should be quoted, at least in the above case, perhaps others, though I can't think of any.

To Reproduce
https://pypi.org/project/composition/8!6.75309/

My Platform
Firefox 80.0b2 (64-bit), macOS

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[di]

Thanks for the report! We probably want to do this conditionally based on whether the version contains an epoch.

(I've added the "good first issue" label to this issue)

[dstufft]

Another option is to quote it all the time, but have the copy/paste button inject the quotes, and leave the visible display alone.