While some fret noise and string squeak is fine, too much, generally from less than stellar playing technique, can be distracting.
Practice playing with better finger technique to lessen it some.... but even the best players have it so it's part of the performance.
If it falls into the "too much of a distraction" camp..... here are a few things I do to "clean up" breath and string noises in a track.
Zoom in on the track so you have maybe one or two, three at the most measures displayed in the track view. Move that track to the top near the time line. Immediately under the time line. Now, hit playback and when you hear the offending noise. Click the time line and stop the playback at the same time. You should be able to clearly see the part of the wave form that contains the squeak. It is usually independent from the music. (it is it's own little blob in the wave)
On the track.... be sure you have selected it by clicking on the one track you are working on. It should be darker to indicate it's selected. So now, simply click and drag on the time line above the track. You should see the selected part of the track highlight darker. Be sure you only get the squeak into that highlighted section. If you miss the mark, no problem, simply drag a second, or third, or fourth time to get the highlighted section to encompass the noise only.
Once that is selected surgically..... use the process audio and choose gain reduction to lower the noise level (assuming you want to keep it) or choose MUTE to silence it totally. Click OK.
In this mode, you can always select EDIT>UNDO and go back if you don't like the result.
Move the time line back and play through the newly processed point. If you like it, go to the next one and repeat the process. Save the project about every three or four edits, and at the end.
I use this exact process all the time with breath noises and other things that I want to remove from the track. It works very well.
If you are concerned about the non-reversable factor involved once you close the project.... yes it is destructive editing once the project is closed since you lose the ability to undo at that point... simply make a clone of the track before you start. You can always delete the clone later once you are 100% satisfied with the edits.