Fix linting errors in projects.md

Fix linting errors in https://docs.gitlab.com/ee/api/projects.html

300:65    error  Avoid using future tense: "will be". Use present tense instead.      gitlab.FutureTense
2247:100  error  Avoid using future tense: "will reject". Use present tense instead.  gitlab.FutureTense
2270:100  error  Avoid using future tense: "will reject". Use present tense instead.  gitlab.FutureTense

If you'd like to work on this issue, mention @msedlakjakubowski in a comment. Then, in your merge request's description, paste this issue's URL so they become linked.

Edited Dec 01, 2020 by Marcin Sedlak-Jakubowski