[tools] Install CIPD ninja using DEPS

[swift-kim]

The ninja binary is being removed from depot_tools.

https://bugs.chromium.org/p/chromium/issues/detail?id=1340825

Fixes the following error.

depot_tools/ninja.py: Could not find Ninja in the third_party of the current project, nor in your PATH.
Please take a following action to install Ninja.
- If your project has DEPS, Add a CIPD Ninja dependency to DEPS.
- Oterweise, Add Ninja to your PATH *after* depot_tools.
Error: Process completed with exit code 1.