Discourage typo fixes in PR template

[tjjfvi]

Wording taken from this comment.

There have been a number of rejected typo fix PRs lately; hopefully this can reduce the amount of typo-fix-rejecting work for the team.

[typescript-bot]

This PR doesn't have any linked issues. Please open an issue that references this PR. From there we can discuss and prioritise.

[orta]

I'll green it, but IMO we should remove:

The same generally applies to other projects.

Because almost all advice for people getting started with OSS is to do this sort of change ( I've given that advice, and I'd give it again in the future ) as it's normally a cheap way to get used to the process

[RyanCavanaugh]

I like the spirit but feel the text is a bit strong. How about

** Typo Fixes **
Please don't send a PR solely for the purpose of fixing a typo, unless that typo truly hurts understanding of the text. Each PR represents work for the maintainers, and that work should provide commensurate value.

If you're interested in sending a PR, the issue tracker has many issues marked `help wanted`.

[DanielRosenwasser]

Maybe a mash-up?

We understand that typo fixes are nice, but when unless these typos
truly make the text harder to read, these typo fixes often ust
add work to the core team without providing much value. If you're interested in
sending a PR, the issue tracker has many issues marked `help wanted`.

Go with Ryan's version unless he likes this one better.

[tjjfvi]

Edited to Ryan's version; I'll change it to Daniel's if desired.

[orta]

Yeah, lets do this 👍🏻