[Fleet] fix edit package policy navigation (elastic#187463)

## Summary

Closes elastic#187336

Fix navigating back to Integration policies list after
Cancelling/Submitting the Edit integration policy page.

See steps to verify in the linked issue.

<img width="1119" alt="image"
src="https://github.com/elastic/kibana/assets/90178898/f89028a6-ef71-4b25-aabc-4f80cb36214b">
<img width="1123" alt="image"
src="https://github.com/elastic/kibana/assets/90178898/e844344c-caff-45ee-9ce7-772ba672e328">

x-pack/plugins/fleet/public/applications/fleet/sections/agent_policy/edit_package_policy_page/index.tsx

@@ -184,24 +184,23 @@ export const EditPackagePolicyForm = memo<{
   //  if `from === 'edit'` then it links back to Policy Details
   //  if `from === 'package-edit'`, or `upgrade-from-integrations-policy-list` then it links back to the Integration Policy List
   const cancelUrl = useMemo((): string => {
-    if (packageInfo && policyId) {
-      return from === 'package-edit'
-        ? getHref('integration_details_policies', {
-            pkgkey: pkgKeyFromPackageInfo(packageInfo!),
-          })
-        : getHref('policy_details', { policyId });
-    }
-    return '/';
+    return from === 'package-edit' && packageInfo
+      ? getHref('integration_details_policies', {
+          pkgkey: pkgKeyFromPackageInfo(packageInfo!),
+        })
+      : policyId
+      ? getHref('policy_details', { policyId })
+      : '/';
   }, [from, getHref, packageInfo, policyId]);
   const successRedirectPath = useMemo(() => {
-    if (packageInfo && policyId) {
-      return from === 'package-edit' || from === 'upgrade-from-integrations-policy-list'
-        ? getHref('integration_details_policies', {
-            pkgkey: pkgKeyFromPackageInfo(packageInfo!),
-          })
-        : getHref('policy_details', { policyId });
-    }
-    return '/';
+    return (from === 'package-edit' || from === 'upgrade-from-integrations-policy-list') &&
+      packageInfo
+      ? getHref('integration_details_policies', {
+          pkgkey: pkgKeyFromPackageInfo(packageInfo!),
+        })
+      : policyId
+      ? getHref('policy_details', { policyId })
+      : '/';
   }, [from, getHref, packageInfo, policyId]);
 
   useHistoryBlock(isEdited);