build(deps): Bump taskcluster from 24.3.1 to 25.2.0 in /tools (mozilla#474)

Bumps [taskcluster](https://github.com/taskcluster/taskcluster) from 24.3.1 to 25.2.0.
- [Release notes](https://github.com/taskcluster/taskcluster/releases)
- [Changelog](https://github.com/taskcluster/taskcluster/blob/master/CHANGELOG.md)
- [Commits](taskcluster/taskcluster@v24.3.1...v25.2.0)

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

Author: dependabot-preview[bot]

tools/requirements.txt

@@ -7,6 +7,6 @@ logbook==1.5.3
 multidict==4.5.2
 raven==6.10.0
 structlog==20.1.0
-taskcluster==24.3.1
+taskcluster==25.2.0
 treeherder-client==5.0.0
 yarl==1.3.0