update eslint, jest, and yarn.lock - see comments

Merge branch 'brodybits-update-eslint-jest-and-yarn-lock'

Seems to resolve yarn audit issues to date.

These updates were made in separate commits in order to avoid
excessively large git commits.

Author: Christopher J. Brody

package.json

@@ -58,13 +58,13 @@
     "@stryker-mutator/core": "^3.1.0",
     "@stryker-mutator/javascript-mutator": "^3.1.0",
     "@stryker-mutator/jest-runner": "^3.1.0",
-    "eslint": "^6.4.0",
-    "eslint-config-standard": "^14.1.0",
-    "eslint-plugin-import": "^2.18.2",
-    "eslint-plugin-node": "^11.0.0",
+    "eslint": "^6.8.0",
+    "eslint-config-standard": "^14.1.1",
+    "eslint-plugin-import": "^2.20.2",
+    "eslint-plugin-node": "^11.1.0",
     "eslint-plugin-promise": "^4.2.1",
     "eslint-plugin-standard": "^4.0.1",
-    "jest": "^24.9.0",
+    "jest": "^25.2.4",
     "recursive-readdir": "^2.2.2"
   }
 }