use shared eslint (#148)

manually fixed 2 non auto-fixable issues in HttpServiceImpl with the tsdoc
all other issues were auto-fixed

3 license issues are introduced (through `argparse`, `axe-core`, and `language-subtag-registry`), but they are all on the approved licenses spreadsheet and are fine with legal since we have added the license preamble for the `language-subtag-registry` in this PR.

J=SLAP-2003, SLAP-2064
TEST=build

.eslintrc.js

@@ -1,30 +1,7 @@
 module.exports = {
-  parser: '@typescript-eslint/parser',
-  parserOptions: {
-    ecmaVersion: 2020,
-    sourceType: 'module'
-  },
   extends: [
-    'plugin:@typescript-eslint/recommended'
+    '@yext/slapshot/typescript'
   ],
-  rules: {
-    indent: ['error', 2],
-    'no-trailing-spaces' : ['error'],
-    'no-multi-spaces' : ['error'],
-    quotes: ['error', 'single'],
-    'space-before-function-paren': ['error', {
-      named: 'never',
-      anonymous: 'never'
-    }],
-    'quote-props': ['error', 'as-needed'],
-    'max-len': ['error', {
-      code: 110,
-      ignorePattern: '^import\\s.+\\sfrom\\s.+;$'
-    }],
-    '@typescript-eslint/semi': ['error'],
-    '@typescript-eslint/type-annotation-spacing': ['error'],
-    '@typescript-eslint/no-unused-vars': ['error', { varsIgnorePattern: '^_' }],
-  },
   overrides: [
     {
       files: ['src/transformers/**/*.ts'],

LICENSE

@@ -1,6 +1,12 @@
+The Answers Core files listed in this repository are licensed under the below license.  All other features and products are subject to separate agreements
+and certain functionality requires paid subscriptions to Yext products.
+
+Contains information from the language-subtag-registry JSON Database (https://github.com/mattcg/language-subtag-registry/tree/master/data/json)
+which is made available under the ODC Attribution License (https://github.com/mattcg/language-subtag-registry/blob/master/LICENSE.md).
+
 BSD 3-Clause License
 
-Copyright (c) 2021, Yext
+Copyright (c) 2022, Yext
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without