Bump io.openapiprocessor:build-plugins from 2026.1 to 2026.3

Bumps io.openapiprocessor:build-plugins from 2026.1 to 2026.3.

---
updated-dependencies:
- dependency-name: io.openapiprocessor:build-plugins
  dependency-version: '2026.3'
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -4,7 +4,7 @@ processor = "2026.3-SNAPSHOT"
 kotlin = "2.3.20"
 target-jdk = "11"
 build-jdk = "17"
-build-plugins = "2026.1"
+build-plugins = "2026.3"
 
 api = "2024.2"
 base = "2026.3-SNAPSHOT"