Fix broken link in PROPOSALS.md

Author: cdsmith

proposals/PROPOSALS.md

@@ -52,7 +52,7 @@ Before submitting a HFTP, it is required that you perform necessary preparations
 
 ### Submission
 
-A HFTP is a Markdown document written in conformance with the [process template](https://github.com/haskellfoundation/tech-proposals/blob/main/TEMPLATE.md). When such changes significantly alter an existing library or tool, the author is invited to provide a proof of concept. Delivering a basic implementation can speed up the process dramatically. If your changes are big or somewhat controversial, don’t let people hypothesize about them and show results upfront. Additionally, it would be ideal if the author of the proposal reached out to any stakeholders (e.g. library authors, maintainers) affected by the proposal and bring them into the formal discussion at this point.
+A HFTP is a Markdown document written in conformance with the [process template](https://github.com/haskellfoundation/tech-proposals/blob/main/proposals/TEMPLATE.md). When such changes significantly alter an existing library or tool, the author is invited to provide a proof of concept. Delivering a basic implementation can speed up the process dramatically. If your changes are big or somewhat controversial, don’t let people hypothesize about them and show results upfront. Additionally, it would be ideal if the author of the proposal reached out to any stakeholders (e.g. library authors, maintainers) affected by the proposal and bring them into the formal discussion at this point.
 
 A HFTP is submitted as a pull request against [the official Haskell tech proposal
 repo](https://github.com/haskellfoundation/tech-proposals). Within a week of receiving the pull request, members of the HFTT will acknowledge your submission, validate that it conforms to the proposal template guidelines (see: [TEMPLATE.md](TEMPLATE.md)) and provide feedback to improve the overall quality of the document (if necessary). When the document conforms to the template guidelines, it is ready for formal evaluation by the HFTT members, as well as the broader community.