chore(deps)(deps): bump com.google.cloud:google-cloud-core (#421)

Bumps com.google.cloud:google-cloud-core from 2.72.0 to 2.73.0.

---
updated-dependencies:
- dependency-name: com.google.cloud:google-cloud-core
  dependency-version: 2.73.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Uladzimir Klyshevich <istin2007@gmail.com>
Co-authored-by: ai-teammate <agent.ai.native@gmail.com>

Author: 3 people

dmtools-core/build.gradle

@@ -131,7 +131,7 @@ dependencies {
 
     // Google Cloud authentication for Vertex AI
     api 'com.google.auth:google-auth-library-oauth2-http:1.50.0'
-    api 'com.google.cloud:google-cloud-core:2.72.0'
+    api 'com.google.cloud:google-cloud-core:2.73.0'
 
     // TOON format serialization for LLM-optimized CLI output (2.0.0 uses Jackson 3.1.3+)
     api 'dev.toonformat:jtoon:2.0.1'