Bump biz.aQute.bnd.gradle from 6.3.1 to 6.4.0

Bumps [biz.aQute.bnd.gradle](https://github.com/bndtools/bnd) from 6.3.1 to 6.4.0.
- [Release notes](https://github.com/bndtools/bnd/releases)
- [Changelog](https://github.com/bndtools/bnd/blob/master/docs/ADDING_RELEASE_DOCS.md)
- [Commits](bndtools/bnd@6.3.1...6.4.0)

---
updated-dependencies:
- dependency-name: biz.aQute.bnd:biz.aQute.bnd.gradle
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

build.gradle

@@ -17,7 +17,7 @@ buildscript {
         classpath "org.asciidoctor:asciidoctor-gradle-jvm:$asciidoctorGradlePluginVersion"
         classpath 'org.asciidoctor:asciidoctorj-pdf:2.3.3'
         classpath "org.beryx:badass-jar:2.0.0"
-        classpath 'biz.aQute.bnd:biz.aQute.bnd.gradle:6.3.1'
+        classpath 'biz.aQute.bnd:biz.aQute.bnd.gradle:6.4.0'
         classpath "io.codearte.gradle.nexus:gradle-nexus-staging-plugin:0.30.0"
     }
 }