chore(deps): update dependency @sourcegraph/tsconfig to v4

Author: renovate-bot

package.json

@@ -119,7 +119,7 @@
     "@commitlint/config-conventional": "^11.0.0",
     "@sourcegraph/eslint-config": "^0.20.8",
     "@sourcegraph/prettierrc": "^3.0.3",
-    "@sourcegraph/tsconfig": "^3.0.0",
+    "@sourcegraph/tsconfig": "^4.0.1",
     "@types/mocha": "7.0.2",
     "@types/node": "12.7.3",
     "@types/sinon": "9.0.10",

yarn.lock

@@ -1175,10 +1175,10 @@
   resolved "https://registry.npmjs.org/@sourcegraph/prettierrc/-/prettierrc-3.0.3.tgz#51bfa9b2588fe35121593fa877143e6373028289"
   integrity sha512-FQ1/Ued4I02R0JkrHHofDN163juVxUnPALzfxPZrDZUHv+c3jHjfZhmTHEz+Wd+g3b7MFk0fkj36nZSnvPyU8A==
 
-"@sourcegraph/tsconfig@^3.0.0":
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/@sourcegraph/tsconfig/-/tsconfig-3.0.0.tgz#dfd8a0072d55a219118f58cfbca71336b58991b2"
-  integrity sha512-/2Q4lAQvHPGkddV7+4FRBgJPIzWw0e364kYq3IkD22H9eHJdA0KHfKXAKmWQjbtVpWSQeNPyVJ1pT5emfef4TQ==
+"@sourcegraph/tsconfig@^4.0.1":
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/@sourcegraph/tsconfig/-/tsconfig-4.0.1.tgz#5965ec41771d2ac5b23b6e0d919cee3e70485840"
+  integrity sha512-G/xsejsR84G5dj3kHJ7svKBo9E5tWl96rUHKP94Y2UDtA7BzUhAYbieM+b9ZUpIRt66h3+MlYbG5HK4UI2zDzw==
 
 "@types/color-name@^1.1.1":
   version "1.1.1"