Stop linking to MSC2324 in the proposal template

proposals/0000-proposal-template.md

@@ -102,16 +102,18 @@ do not consider vulnerabilities with their design, we rely on reviewers to consi
 is easy to forget, so having a mandatory 'Security Considerations' section serves to nudge reviewers
 into thinking like an attacker.
 
+
 ## Unstable prefix
 
 *If a proposal is implemented before it is included in the spec, then implementers must ensure that the
 implementation is compatible with the final version that lands in the spec. This generally means that
 experimental implementations should use `/unstable` endpoints, and use vendor prefixes where necessary.
-For more information, see [MSC2324](https://github.com/matrix-org/matrix-doc/pull/2324). This section
+For more information, see https://spec.matrix.org/proposals/#early-release-of-an-mscidea. This section
 should be used to document things such as what endpoints and names are being used while the feature is
 in development, the name of the unstable feature flag to use to detect support for the feature, or what
 migration steps are needed to switch to newer versions of the proposal.*
 
+
 ## Dependencies
 
 This MSC builds on MSCxxxx, MSCyyyy and MSCzzzz (which at the time of writing have not yet been accepted