Bump tycho.version from 1.6.0 to 2.6.0 in /ddk-parent

Bumps `tycho.version` from 1.6.0 to 2.6.0.

Updates `tycho-maven-plugin` from 1.6.0 to 2.6.0
- [Release notes](https://github.com/eclipse/tycho/releases)
- [Changelog](https://github.com/eclipse/tycho/blob/master/RELEASE_NOTES.md)
- [Commits](eclipse-tycho/tycho@tycho-1.6.0...tycho-2.6.0)

Updates `target-platform-configuration` from 1.6.0 to 2.6.0
- [Release notes](https://github.com/eclipse/tycho/releases)
- [Changelog](https://github.com/eclipse/tycho/blob/master/RELEASE_NOTES.md)
- [Commits](eclipse-tycho/tycho@tycho-1.6.0...tycho-2.6.0)

Updates `tycho-compiler-plugin` from 1.6.0 to 2.6.0
- [Release notes](https://github.com/eclipse/tycho/releases)
- [Changelog](https://github.com/eclipse/tycho/blob/master/RELEASE_NOTES.md)
- [Commits](eclipse-tycho/tycho@tycho-1.6.0...tycho-2.6.0)

Updates `tycho-packaging-plugin` from 1.6.0 to 2.6.0
- [Release notes](https://github.com/eclipse/tycho/releases)
- [Changelog](https://github.com/eclipse/tycho/blob/master/RELEASE_NOTES.md)
- [Commits](eclipse-tycho/tycho@tycho-1.6.0...tycho-2.6.0)

Updates `tycho-surefire-plugin` from 1.6.0 to 2.6.0

Updates `tycho-source-plugin` from 1.6.0 to 2.6.0
- [Release notes](https://github.com/eclipse/tycho/releases)
- [Changelog](https://github.com/eclipse/tycho/blob/master/RELEASE_NOTES.md)
- [Commits](eclipse-tycho/tycho@tycho-1.6.0...tycho-2.6.0)

Updates `tycho-source-feature-plugin` from 1.6.0 to 2.6.0

Updates `tycho-versions-plugin` from 1.6.0 to 2.6.0

---
updated-dependencies:
- dependency-name: org.eclipse.tycho:tycho-maven-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.eclipse.tycho:target-platform-configuration
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.eclipse.tycho:tycho-compiler-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.eclipse.tycho:tycho-packaging-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.eclipse.tycho:tycho-surefire-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.eclipse.tycho:tycho-source-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.eclipse.tycho.extras:tycho-source-feature-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.eclipse.tycho:tycho-versions-plugin
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

ddk-parent/pom.xml

@@ -54,7 +54,7 @@
     <spotbugs.version>4.5.3</spotbugs.version>
     <pmd.plugin.version>3.15.0</pmd.plugin.version>
     <pmd.version>6.42.0</pmd.version>
-    <tycho.version>1.6.0</tycho.version>
+    <tycho.version>2.6.0</tycho.version>
     <xtend.version>2.25.0</xtend.version>
   </properties>