prepare for v0.13.0 (#1395)

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# Description

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Please also include relevant motivation and context. -->

Prepare for v0.13.0 release.

### Improvements

- Codegen: pluginDownloadURL is now supported through the automatically
generated build.gradle
- Update pulumi/pulumi to v3.121.0

### Bug Fixes

- Unable to rehydrate a resource that has required inputs

CHANGELOG.md

@@ -1,11 +1,16 @@
 CHANGELOG
 =========
 
-## Unreleased
+## 0.13.0 (2024-07-29)
 
 ### Improvements
 
-- Update pulumi/pulumi to v3.121.0.
+- Codegen: pluginDownloadURL is now supported through the automatically generated build.gradle
+- Update pulumi/pulumi to v3.121.0
+
+### Bug Fixes
+
+- Unable to rehydrate a resource that has required inputs
 
 ## 0.12.0 (2024-05-24)
 

CHANGELOG_PENDING.md

@@ -1,7 +1,5 @@
 ### Improvements
 
-- Codegen: pluginDownloadURL is now supported through the automatically generated build.gradle
 
 ### Bug Fixes
 
-- Unable to rehydrate a resource that has required inputs