fix(changelog): remove release which does not exist (#3214)

Author: devoto13

CHANGELOG.md

@@ -57,23 +57,6 @@
 
 
 
-<a name="2.0.6"></a>
-## [2.0.6](https://github.com/karma-runner/karma/compare/v2.0.5...v2.0.6) (2018-08-09)
-
-
-### Bug Fixes
-
-* **config:** wait 20s for browser activity. ([#3087](https://github.com/karma-runner/karma/issues/3087)) ([88b977f](https://github.com/karma-runner/karma/commit/88b977f))
-* **config:** Wait 30s for browser activity per Travis. ([#3091](https://github.com/karma-runner/karma/issues/3091)) ([f6d2f0e](https://github.com/karma-runner/karma/commit/f6d2f0e))
-* **init:** add "ChromeHeadless" to the browsers' options ([#3096](https://github.com/karma-runner/karma/issues/3096)) ([56fda53](https://github.com/karma-runner/karma/commit/56fda53))
-* **server:** Exit clean on unhandledRejections. ([#3092](https://github.com/karma-runner/karma/issues/3092)) ([02f54c6](https://github.com/karma-runner/karma/commit/02f54c6)), closes [#3064](https://github.com/karma-runner/karma/issues/3064)
-* **travis:** Up the socket timeout 2->20s. ([#3103](https://github.com/karma-runner/karma/issues/3103)) ([732396a](https://github.com/karma-runner/karma/commit/732396a)), closes [#3102](https://github.com/karma-runner/karma/issues/3102)
-* **travis:** use the value not the key name. ([#3097](https://github.com/karma-runner/karma/issues/3097)) ([90f5546](https://github.com/karma-runner/karma/commit/90f5546))
-* **travis:** validate TRAVIS_COMMIT if TRAVIS_PULL_REQUEST_SHA is not set. ([#3094](https://github.com/karma-runner/karma/issues/3094)) ([fba5d36](https://github.com/karma-runner/karma/commit/fba5d36))
-* **travis:** Validate TRAVIS_PULL_REQUEST_SHA rather than TRAVIS_COMMIT. ([#3093](https://github.com/karma-runner/karma/issues/3093)) ([a58fa45](https://github.com/karma-runner/karma/commit/a58fa45))
-
-
-
 <a name="2.0.5"></a>
 ## [2.0.5](https://github.com/karma-runner/karma/compare/v2.0.4...v2.0.5) (2018-07-24)