Fix sources.list.d deb: make 64bit explicit to avoid warning

[janos-r]

Issue

Description

Since all Bruno releases are 64bit, there is no reason to skip this argument. Without it, apt gives a warning on every run: N: Skipping acquire of configured file 'stable/binary-i386/Packages' as repository 'http://debian.usebruno.com bruno InRelease' doesn't support architecture 'i386'

Contribution Checklist:

• [x] The pull request only addresses one issue or adds one feature.
• [x] The pull request does not introduce any breaking changes
• [x] I have added screenshots or gifs to help explain the change if applicable.
• [x] I have read the contribution guidelines.
• [x] Create an issue and link to the pull request.

before:

after: