servo: Merge #12511 - Added test-tidy for dependent licenses (from asajeffrey:test-tidy-dep-licenses); r=larsbergstrom

<!-- Please describe your changes on the following line: -->

Add a test-tidy lint for dependency licenses. Note that #12507 should land first.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because we don't test our lints

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Source-Repo: https://github.com/servo/servo
Source-Revision: de4eaa4f21c53a1d1da7d58ef2cda8ef28989fb6

servo/python/tidy/servo_tidy/licenseck.py

@@ -88,3 +88,38 @@ licenses_toml = [
     'license = "MPL-2.0"',
     'license = "MIT/Apache-2.0"',
 ]
+
+# The valid dependency licenses, in the form we'd expect to see them in a Cargo.toml file.
+licenses_dep_toml = [
+    # Licenses that are compatible with Servo's licensing
+    'license = "Apache-2 / MIT"',
+    'license = "Apache-2.0 / MIT"',
+    'license = "Apache-2.0"',
+    'license = "Apache-2.0/MIT"',
+    'license = "BSD-2-Clause"',
+    'license = "BSD-3-Clause"',
+    'license = "BSD-3-Clause/MIT"',
+    'license = "CC0-1.0"',
+    'license = "ISC"',
+    'license = "MIT / Apache-2.0"',
+    'license = "MIT OR Apache-2.0"',
+    'license = "MIT"',
+    'license = "MIT/Apache-2.0"',
+    'license = "MPL-2.0"',
+    'license = "Unlicense/MIT"',
+    'license = "zlib-acknowledgement"',
+    'license-file = "LICENSE-MIT"',
+    'license=  "MIT / Apache-2.0"',
+    # Whitelisted crates whose licensing has been checked manually
+    'name = "device"',
+    'name = "dylib"',
+    'name = "ipc-channel"',
+    'name = "mozjs_sys"',
+    'name = "azure"',
+    'name = "freetype"',
+    'name = "js"',
+    'name = "servo-freetype-sys"',
+    'name = "simd"',
+    'name = "webrender"',
+    'name = "webrender_traits"',
+]