cordova-common singleton rule N/A since Cordova 9

(does not apply since cordova-common@3.1.0)
diff --git a/docs/tools-release-process.md b/docs/tools-release-process.md
index 9f37240..c8a21ab 100644
--- a/docs/tools-release-process.md
+++ b/docs/tools-release-process.md
@@ -36,6 +36,8 @@
 
 ### cordova-common singleton rule
 
+**Does not apply since Cordova 9 (cordova-common@3.1.0):**
+
 The most important rule is that packages such as `cordova-lib` and `cordova-cli` should not use multiple versions of `cordova-common` through the chain of dependencies. This rule is due to the use of multiple singletons in `cordova-common`. This means that if `cordova-common` is updated it should be released before other packages such as `cordova-fetch`, `cordova-create`, `cordova-lib`, `cordova-cli`, etc.
 
 ### Alternative approaches