Change how Bitbucket auth variables are shown

[RCdeWit]

While following the getting started docs for CML on Bitbucket, I ran into an issue because I generated the REPO_TOKEN incorrectly. I made a mistake while following echo -n $USERNAME:$PASSWORD | base64; left in the first $.

$USERNAME and $PASSWORD are not necessarily variables that are set when the user runs this command. Worst case, the local $USERNAME is different from the Bitbucket username.

I am not sure if my proposed solution is the ideal one, but earlier in this page we use {} to denote that the user should specify a variable here. Maybe we could use that approach here too.

[github-actions[bot]]

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[dacbd]

We should probably give other areas of the docs a scrub to be consistent, @jorgeorpinel do the DVC docs have a consistent format for this same type thing?

[jorgeorpinel]

Yes, we try to be consistent in general. Even in hypothetic metavars for remote modify param samples, for example. But it can be tricky. Probably worth it if someone is running into issues due to inconsistent formatting though.