Reformat http-client-java test spec for heritage formatter change

arm-customization.tsp now keeps `is` inline on its `TrackedResourceWithOptionalLocation`
base, matching the compiler formatter change (#11009). Whitespace only, no
semantic change.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: oha-4

.chronus/changes/fix-formatter-heritage-keyword-break-java-2026-6-18.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@typespec/http-client-java"
+---
+
+Reformat a test spec affected by the compiler formatter change keeping `is`/`extends` inline for multi-argument template references (whitespace only, no semantic change).

packages/http-client-java/generator/http-client-generator-test/tsp/arm-customization.tsp

@@ -23,8 +23,10 @@ enum Versions {
   v2023_12_01_preview: "2023-12-01-preview",
 }
 
-model Vault
-  is Azure.ResourceManager.Legacy.TrackedResourceWithOptionalLocation<VaultProperties, false> {
+model Vault is Azure.ResourceManager.Legacy.TrackedResourceWithOptionalLocation<
+  VaultProperties,
+  false
+> {
   ...ResourceNameParameter<
     Resource = Vault,
     KeyName = "vaultName",