Bump com.github.spotbugs from 6.0.15 to 6.0.18

Bumps com.github.spotbugs from 6.0.15 to 6.0.18.

---
updated-dependencies:
- dependency-name: com.github.spotbugs
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

build.gradle.kts

@@ -8,7 +8,7 @@ import java.util.zip.ZipFile
 
 plugins {
     id("org.jenkins-ci.jpi") version "0.50.0"
-    id("com.github.spotbugs") version "6.0.15"
+    id("com.github.spotbugs") version "6.0.18"
     id("codenarc")
     id("buildlogic.reproducible-archives")
 }