chore(rsbuild): add migration notes

packages/rsbuild/src/utils/versions.ts

@@ -4,5 +4,13 @@ export const rsbuildPluginReactVersion = '1.1.0';
 export const rsbuildPluginSassVersion = '1.1.2';
 export const rsbuildPluginLessVersion = '1.1.0';
 export const rsbuildPluginStyledComponentsVersion = '1.1.0';
+
+/**
+ * These versions need to line up with the version of the swc_core crate Rspack uses for the version of Rsbuild above
+ * Checking the `cargo.toml` at https://github.com/web-infra-dev/rspack/blob/main/Cargo.toml for the correct Rspack version
+ * is the best way to ensure that these versions are correct.
+ *
+ * The release notes for the packages below are very helpful in understanding what version of swc_core crate they require.
+ */
 export const rsbuildSwcPluginEmotionVersion = '^7.0.3';
 export const rsbuildSwcPluginStyledJsxVersion = '^5.0.2';