chore(deps): update dependency @types/chai to v4.2.8

Author: renovate-bot

package.json

@@ -42,7 +42,7 @@
     "@sourcegraph/prettierrc": "^3.0.2",
     "@sourcegraph/tsconfig": "^4.0.0",
     "@sourcegraph/tslint-config": "^13.4.0",
-    "@types/chai": "4.2.7",
+    "@types/chai": "4.2.8",
     "@types/fs-extra": "7.0.0",
     "@types/karma": "3.0.5",
     "@types/karma-webpack": "2.0.7",

yarn.lock

@@ -420,10 +420,10 @@
   resolved "https://registry.yarnpkg.com/@types/bluebird/-/bluebird-3.5.24.tgz#11f76812531c14f793b8ecbf1de96f672905de8a"
   integrity sha512-YeQoDpq4Lm8ppSBqAnAeF/xy1cYp/dMTif2JFcvmAbETMRlvKHT2iLcWu+WyYiJO3b3Ivokwo7EQca/xfLVJmg==
 
-"@types/[email protected].7":
-  version "4.2.7"
-  resolved "https://registry.yarnpkg.com/@types/chai/-/chai-4.2.7.tgz#1c8c25cbf6e59ffa7d6b9652c78e547d9a41692d"
-  integrity sha512-luq8meHGYwvky0O7u0eQZdA7B4Wd9owUCqvbw2m3XCrCU8mplYOujMBbvyS547AxJkC+pGnd0Cm15eNxEUNU8g==
+"@types/[email protected].8":
+  version "4.2.8"
+  resolved "https://registry.yarnpkg.com/@types/chai/-/chai-4.2.8.tgz#c8d645506db0d15f4aafd4dfa873f443ad87ea59"
+  integrity sha512-U1bQiWbln41Yo6EeHMr+34aUhvrMVyrhn9lYfPSpLTCrZlGxU4Rtn1bocX+0p2Fc/Jkd2FanCEXdw0WNfHHM0w==
 
 "@types/connect@*":
   version "3.4.32"