add migration path

Author: stamat

.changeset/old-bears-admire.md

@@ -1,6 +1,13 @@
 ---
-"@primer/brand-primitives": patch
-"@primer/react-brand": patch
+'@primer/brand-primitives': patch
+'@primer/react-brand': patch
 ---
 
 Remove the hover text-decoration transition in `InlineLink`, `Accordion`, `Timeline` and align `Prose` with the updated `InlineLink` styles
+
+In case you were using `var(--brand-InlineLink-transition-timing)` variable please migrate to `var(--brand-animation-duration-fast)`
+
+```diff
+- var(--brand-InlineLink-transition-timing)
++ var(--brand-animation-duration-fast)
+```