Bump org.codehaus.mojo:flatten-maven-plugin in /ladybug-test-webapp (#896)

Bumps [org.codehaus.mojo:flatten-maven-plugin](https://github.com/mojohaus/flatten-maven-plugin) from 1.7.3 to 1.8.0.
- [Release notes](https://github.com/mojohaus/flatten-maven-plugin/releases)
- [Commits](mojohaus/flatten-maven-plugin@1.7.3...1.8.0)

---
updated-dependencies:
- dependency-name: org.codehaus.mojo:flatten-maven-plugin
  dependency-version: 1.8.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

pom.xml

@@ -485,7 +485,7 @@
         <plugin>
           <groupId>org.codehaus.mojo</groupId>
           <artifactId>flatten-maven-plugin</artifactId>
-          <version>1.7.3</version>
+          <version>1.8.0</version>
           <configuration>
             <updatePomFile>true</updatePomFile>
             <flattenMode>resolveCiFriendliesOnly</flattenMode>