fix: package.json, yarn.lock & .snyk to reduce vulnerabilities

The following vulnerabilities are fixed with a Snyk patch:
- https://snyk.io/vuln/SNYK-JS-LODASH-567746

.snyk

@@ -0,0 +1,8 @@
+# Snyk (https://snyk.io) policy file, patches or ignores known vulnerabilities.
+version: v1.15.0
+ignore: {}
+# patches apply the minimum changes required to fix a vulnerability
+patch:
+  SNYK-JS-LODASH-567746:
+    - lodash:
+        patched: '2020-06-16T05:18:19.258Z'

package.json

@@ -1,57 +1,61 @@
 {
-    "name": "hydrooj",
-    "version": "2.2.1",
-    "main": "hydro/loader.js",
-    "repository": "https://github.com/hydro-dev/Hydro.git",
-    "author": "masnn",
-    "license": "GPL-3.0-only",
-    "dependencies": {
-        "adm-zip": "^0.4.14",
-        "axios": "^0.19.0",
-        "bson": "^4.0.2",
-        "js-yaml": "^3.13.1",
-        "koa": "^2.11.0",
-        "koa-body": "^4.1.1",
-        "koa-morgan": "^1.0.1",
-        "koa-router": "^8.0.8",
-        "koa-static-cache": "^5.1.3",
-        "lodash": "^4.17.15",
-        "markdown-it": "^10.0.0",
-        "markdown-it-container": "^3.0.0",
-        "markdown-it-footnote": "^3.0.2",
-        "markdown-it-imsize": "^2.0.1",
-        "markdown-it-katex": "^2.0.3",
-        "markdown-it-mark": "^3.0.0",
-        "moment-timezone": "^0.5.31",
-        "mongodb": "^3.5.7",
-        "nodemailer": "^6.3.1",
-        "nunjucks": "^3.2.1",
-        "prismjs": "^1.20.0",
-        "sockjs": "^0.3.20",
-        "systeminformation": "^4.26.5"
-    },
-    "devDependencies": {
-        "eslint": "^6.8.0",
-        "eslint-config-airbnb-base": "^14.1.0",
-        "eslint-plugin-import": "^2.20.2",
-        "friendly-errors-webpack-plugin": "^1.7.0",
-        "webpack": "^4.42.1"
-    },
-    "scripts": {
-        "build": "node build/development.js",
-        "build:development": "node build/development.js",
-        "build:production": "node build/production.js",
-        "build:all": "cd ui && yarn && yarn build:production && cd .. && yarn && yarn build:production",
-        "start": "node hydro/loader.js",
-        "pack": "pkg .",
-        "lint": "eslint build hydro module tool --fix"
-    },
-    "pkg": {
-        "scripts": [
-            ".build/app.js"
-        ],
-        "assets": [
-            ".build/module/**"
-        ]
-    }
+  "name": "hydrooj",
+  "version": "2.2.1",
+  "main": "hydro/loader.js",
+  "repository": "https://github.com/hydro-dev/Hydro.git",
+  "author": "masnn",
+  "license": "GPL-3.0-only",
+  "dependencies": {
+    "adm-zip": "^0.4.14",
+    "axios": "^0.19.0",
+    "bson": "^4.0.2",
+    "js-yaml": "^3.13.1",
+    "koa": "^2.11.0",
+    "koa-body": "^4.1.1",
+    "koa-morgan": "^1.0.1",
+    "koa-router": "^8.0.8",
+    "koa-static-cache": "^5.1.3",
+    "lodash": "^4.17.15",
+    "markdown-it": "^10.0.0",
+    "markdown-it-container": "^3.0.0",
+    "markdown-it-footnote": "^3.0.2",
+    "markdown-it-imsize": "^2.0.1",
+    "markdown-it-katex": "^2.0.3",
+    "markdown-it-mark": "^3.0.0",
+    "moment-timezone": "^0.5.31",
+    "mongodb": "^3.5.7",
+    "nodemailer": "^6.3.1",
+    "nunjucks": "^3.2.1",
+    "prismjs": "^1.20.0",
+    "sockjs": "^0.3.20",
+    "systeminformation": "^4.26.5",
+    "snyk": "^1.341.1"
+  },
+  "devDependencies": {
+    "eslint": "^6.8.0",
+    "eslint-config-airbnb-base": "^14.1.0",
+    "eslint-plugin-import": "^2.20.2",
+    "friendly-errors-webpack-plugin": "^1.7.0",
+    "webpack": "^4.42.1"
+  },
+  "scripts": {
+    "build": "node build/development.js",
+    "build:development": "node build/development.js",
+    "build:production": "node build/production.js",
+    "build:all": "cd ui && yarn && yarn build:production && cd .. && yarn && yarn build:production",
+    "start": "node hydro/loader.js",
+    "pack": "pkg .",
+    "lint": "eslint build hydro module tool --fix",
+    "snyk-protect": "snyk protect",
+    "prepare": "yarn run snyk-protect"
+  },
+  "pkg": {
+    "scripts": [
+      ".build/app.js"
+    ],
+    "assets": [
+      ".build/module/**"
+    ]
+  },
+  "snyk": true
 }