fix(clerk-js): Pass signInUrl to sign up context when in combined flow (#5042)

Author: alexcarpenter

.changeset/violet-years-dream.md

@@ -0,0 +1,5 @@
+---
+'@clerk/clerk-js': patch
+---
+
+Pass the `signInUrl` throught to the sign up context when within the combined flow.

packages/clerk-js/src/ui/components/SignIn/SignIn.tsx

@@ -151,6 +151,7 @@ function SignInRoot() {
     ssoCallbackUrl: signInContext.ssoCallbackUrl,
     forceRedirectUrl: signInContext.signUpForceRedirectUrl,
     fallbackRedirectUrl: signInContext.signUpFallbackRedirectUrl,
+    signInUrl: signInContext.signInUrl,
     ...normalizeRoutingOptions({ routing: signInContext?.routing, path: signInContext?.path }),
   } as SignUpContextType;