fix: use searchable=true in SSA e2e test assertion

The API server omits zero-value booleans (searchable: false), causing the
assertion to fail. Use searchable: true for the third field instead.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: scotwells

test/e2e/server-side-apply/chainsaw-test.yaml

@@ -91,7 +91,7 @@ spec:
                   - path: ".spec.email"
                     searchable: true
                   - path: ".spec.phone"
-                    searchable: false
+                    searchable: true
               EOF
             check:
               ($error == null): true
@@ -113,7 +113,7 @@ spec:
                   - path: ".spec.email"
                     searchable: true
                   - path: ".spec.phone"
-                    searchable: false
+                    searchable: true
       catch:
       - describe:
           apiVersion: search.miloapis.com/v1alpha1