Bump io.opentelemetry:opentelemetry-bom from 1.39.0 to 1.40.0

Bumps [io.opentelemetry:opentelemetry-bom](https://github.com/open-telemetry/opentelemetry-java) from 1.39.0 to 1.40.0.
- [Release notes](https://github.com/open-telemetry/opentelemetry-java/releases)
- [Changelog](https://github.com/open-telemetry/opentelemetry-java/blob/main/CHANGELOG.md)
- [Commits](open-telemetry/opentelemetry-java@v1.39.0...v1.40.0)

---
updated-dependencies:
- dependency-name: io.opentelemetry:opentelemetry-bom
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

pom.xml

@@ -41,7 +41,7 @@
     <com.io7m.zelador.version>1.0.0</com.io7m.zelador.version>
 
     <!-- Third-party dependencies. -->
-    <io.opentelemetry.version>1.39.0</io.opentelemetry.version>
+    <io.opentelemetry.version>1.40.0</io.opentelemetry.version>
     <jqwik.version>1.9.0</jqwik.version>
     <org.junit.version>5.10.3</org.junit.version>
     <containers.postgresql.version>16.3</containers.postgresql.version>