Truncate commit message on the branches and prebuilds pages

[gtsiolis]

Problem to solve

Commit message can sometimes overflow into two lines of text in the Branches page.

Proposal

Let's truncate the commit message on the branches and prebuilds pages. 🦊

BEFORE	AFTER

[svenefftinge]

Another truncate issue:

[svenefftinge]

Also this #5332

[gtsiolis]

The branch truncation could be fixed in #5098, see #5098 (comment). 🤿

[gtsiolis]

Updating description as linking to commits is also described in #5923.

[gtsiolis]

/assign @gtsiolis
/team meta
/schedule

[roboquat]

@gtsiolis: Cannot schedule issue - issue does not belong to a team. Use /team to specify one.

In response to this:

/assign @gtsiolis
/team meta
/schedule

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