Bug 1859081 - Move cld2 from toolkit/component/translation to translations; r=translations-reviewers,zeid,frontend-codestyle-reviewers,nordzilla

We developed the new translations codebase using an "s" at the end, and
retained the old translations code under "translation". At this point
I'm unifying it so that it's all under "translations", which involves a
rename of the existing code. This way we will be consistent in our
naming practice.

Differential Revision: https://phabricator.services.mozilla.com/D239047

.clang-format-ignore

@@ -202,7 +202,7 @@ testing/web-platform/tests/tools/third_party/.*
 third_party/.*
 toolkit/components/jsoncpp/.*
 toolkit/components/protobuf/.*
-toolkit/components/translation/cld2/.*
+toolkit/components/translations/cld2/.*
 toolkit/components/url-classifier/chromium/.*
 toolkit/components/url-classifier/protobuf/.*
 toolkit/crashreporter/breakpad-client/.*