Mention exp apply --no-force option in "Persisting Experiments"

[daavoo]

The option is only mentioned in the command reference but we don't have examples or motivations behind the usage.

I think it would be nice to add a mention to the option in the "Persisting Experiments" user guide.

@pmrowla I hadn't noticed the --no-force argument. On reflection, switching between experiments would necessitate use of a --force flag if it existed, and I guess that use-case is considered the most common.

I will monitor how I use exp apply for now, and whether I can easily encorporate --no-force into my workflow.

Originally posted by @mattlbeck in iterative/dvc#6930 (comment)

[jorgeorpinel]

So, I think the default behavior should be definitely noted (that it destroys current changes i.e. the Git working tree) and it is (in the ref), but we could rephrase to make it clearer there.

We should add this explanation to the guide as well. I'm surprised it was left out of https://dvc.org/doc/user-guide/experiment-management/persisting-experiments actually. Did we leave out many other options from guides @iesahin ? Thanks

[iesahin]

As far as I can tell, there is none.