Pipeline failed emails include ANSI escape codes in text/plain part

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Your pipeline has failed.

Project: GitLab Enterprise Edition ( https://gitlab.com/gitlab-org/gitlab-ee )
Branch: nt/ce-to-ee-thursday ( https://gitlab.com/gitlab-org/gitlab-ee/commits/nt/ce-to-ee-thursday )
Merge Request: !1683 ( https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/1683 )

Commit: 6f7be97e ( https://gitlab.com/gitlab-org/gitlab-ee/commit/6f7be97ed5b6ac812482d33d85f27f70643f6132 )
Commit Message: Fix "Fix conflicts in filtered search"

Commit Author: Nick Thomas ( https://gitlab.com/nick.thomas )

Pipeline #7758502 ( https://gitlab.com/gitlab-org/gitlab-ee/pipelines/7758502 ) triggered by Nick Thomas ( https://gitlab.com/nick.thomas )
had 1 failed build.

Job #14710069 ( https://gitlab.com/gitlab-org/gitlab-ee/builds/14710069 )

Stage: test
Name: rake karma
Trace: error "webpack#watchpack" is wrong version: expected "1.3.1", got "1.2.1"
warning "babel-preset-es2015#babel-plugin-transform-es2015-unicode-regex#regexpu-core@^2.0.0" could be deduped from "2.0.0" to "regexpu-core@2.0.0"
warning "babel-generator#detect-indent#repeating@^2.0.0" could be deduped from "2.0.1" to "repeating@2.0.1"
error "sockjs-client#faye-websocket" is wrong version: expected "0.7.3", got "0.11.1"
error "update-notifier#repeating" is wrong version: expected "1.1.3", got "2.0.1"
error Found 26 errors.
Error: You have unmet dependencies. (`yarn check` command failed)
Run `yarn install` to install missing modules.
[31;1mERROR: Job failed: exit code 1
[0;

We should be able to strip these out