Hash (and everything after) in .gitmessage is missing in "Source Control" pre-filled message

[rlebosse]

• VSCode Version: 1.38.0
• OS Version: Ubuntu 18.04.3 LTS

Steps to Reproduce:

1. Write message #issue in file ~/.gitmessage

2. Open VSCode in a project that is linked to git
3. Open "Source Control" section
4. The pre-filled message is only "message " (the hash and everything after is missing)

Does this issue occur when all extensions are disabled?: Yes

The whole message was displayed correctly in the previous VSCode version.

[joaomoreno]

Broken by #71710. The right fix there would just be to remove the call to trim().