DeveloperPolicy: Reword paragraph about contributing without commit access

This change was suggested as a follow-up to
#127006

Author: tstellar

llvm/docs/DeveloperPolicy.rst

@@ -539,8 +539,11 @@ What are the expectations around a revert?
 Obtaining Commit Access
 -----------------------
 
-Once you have 3 or more merged pull requests, you may use this
-link <https://github.com/llvm/llvm-project/issues/new?title=Request%20Commit%20Access%20For%20%3Cuser%3E&body=%23%23%23%20Why%20Are%20you%20requesting%20commit%20access%20?>`_ to file
+LLVM operates using Github Pull Requests. In most cases, contributing
+to the project does not require commit access, as Pull Request reviewers
+can perform the merge once ready. However, contributors are eligible to
+obtain direct commit access to the repository once they have 3 or more
+merged pull requests. To do so, you may use  this `link <https://github.com/llvm/llvm-project/issues/new?title=Request%20Commit%20Access%20For%20%3Cuser%3E&body=%23%23%23%20Why%20Are%20you%20requesting%20commit%20access%20?>`_ to file
 an issue and request commit access. Replace the <user> string in the title
 with your github username, and explain why you are requesting commit access in
 the issue description.  Once the issue is created, you will need to get two
@@ -558,11 +561,6 @@ GitHub account. In case you don't get notification from GitHub, go to
 `Invitation Link <https://github.com/orgs/llvm/invitation>`_ directly. Once
 you accept the invitation, you'll get commit access.
 
-Prior to obtaining commit access, it is common practice to request that
-someone with commit access commits on your behalf. When doing so, please
-provide the name and email address you would like to use in the Author
-property of the commit.
-
 For external tracking purposes, committed changes are automatically reflected
 on a commits mailing list soon after the commit lands (e.g. llvm-commits_).
 Note that these mailing lists are moderated, and it is not unusual for a large