[HealthCheckController] use fs.copyFile instead of fs-extra.copy

the fs-extra method has a HUGE overhead of JS code and also syscalls for
 no particular benefit in this case: just copy the tiny.pdf file.

Here is an overview of the major operations: paths are relative to
  https://github.com/jprichardson/node-fs-extra/blob/1.0.0

We start in /lib/copy/copy.js
- sys: check that the source file exists
- sys: check that the source file has an existing parent directory?!
Continue in /lib/copy/ncp.js
- sys: more stat calls on both source and dest to determine permissions
- read/write streams to pipe the file content through the process
- sys: chmod on the destination to match the source permissions

What we actually need is a call to the binding and let node/the os
 figure out the best way to copy the contents.

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

services/filestore/app/js/HealthCheckController.js

@@ -1,4 +1,4 @@
-const fs = require('fs-extra')
+const fs = require('fs')
 const path = require('path')
 const Settings = require('settings-sharelatex')
 const streamBuffers = require('stream-buffers')
@@ -6,7 +6,7 @@ const { promisify } = require('util')
 const Stream = require('stream')
 
 const pipeline = promisify(Stream.pipeline)
-const fsCopy = promisify(fs.copy)
+const fsCopy = promisify(fs.copyFile)
 const fsUnlink = promisify(fs.unlink)
 
 const { HealthCheckError } = require('./Errors')

services/filestore/package-lock.json

@@ -2488,16 +2488,6 @@
       "resolved": "https://registry.npmjs.org/fresh/-/fresh-0.5.2.tgz",
       "integrity": "sha512-zJ2mQYM18rEFOudeV4GShTGIQ7RbzA7ozbU9I/XBpm7kqgMywgmylMwXHxZJmkVoYkna9d2pVXVXPdYTP9ej8Q=="
     },
-    "fs-extra": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-1.0.0.tgz",
-      "integrity": "sha512-VerQV6vEKuhDWD2HGOybV6v5I73syoc/cXAbKlgTC7M/oFVEtklWlp9QH2Ijw3IaWDOQcMkldSPa7zXy79Z/UQ==",
-      "requires": {
-        "graceful-fs": "^4.1.2",
-        "jsonfile": "^2.1.0",
-        "klaw": "^1.0.0"
-      }
-    },
     "fs.realpath": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/fs.realpath/-/fs.realpath-1.0.0.tgz",
@@ -2644,7 +2634,8 @@
     "graceful-fs": {
       "version": "4.2.3",
       "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.3.tgz",
-      "integrity": "sha512-a30VEBm4PEdx1dRB7MFK7BejejvCvBronbLjht+sHuGYj8PHs7M/5Z+rt5lw551vZ7yfTCj4Vuyy3mSJytDWRQ=="
+      "integrity": "sha512-a30VEBm4PEdx1dRB7MFK7BejejvCvBronbLjht+sHuGYj8PHs7M/5Z+rt5lw551vZ7yfTCj4Vuyy3mSJytDWRQ==",
+      "dev": true
     },
     "growl": {
       "version": "1.10.5",
@@ -3072,14 +3063,6 @@
       "resolved": "https://registry.npmjs.org/json-stringify-safe/-/json-stringify-safe-5.0.1.tgz",
       "integrity": "sha512-ZClg6AaYvamvYEE82d3Iyd3vSSIjQ+odgjaTzRuO3s7toCdFKczob2i0zCh7JE8kWn17yvAWhUVxvqGwUalsRA=="
     },
-    "jsonfile": {
-      "version": "2.4.0",
-      "resolved": "https://registry.npmjs.org/jsonfile/-/jsonfile-2.4.0.tgz",
-      "integrity": "sha512-PKllAqbgLgxHaj8TElYymKCAgrASebJrWpTnEkOaTowt23VKXXN0sUeriJ+eh7y6ufb/CC5ap11pz71/cM0hUw==",
-      "requires": {
-        "graceful-fs": "^4.1.6"
-      }
-    },
     "jsprim": {
       "version": "1.4.1",
       "resolved": "https://registry.npmjs.org/jsprim/-/jsprim-1.4.1.tgz",
@@ -3116,14 +3099,6 @@
         "safe-buffer": "^5.0.1"
       }
     },
-    "klaw": {
-      "version": "1.3.1",
-      "resolved": "https://registry.npmjs.org/klaw/-/klaw-1.3.1.tgz",
-      "integrity": "sha512-TED5xi9gGQjGpNnvRWknrwAB1eL5GciPfVFOt3Vk1OJCVDQbzuSfrF3hkUQKlsgKrG1F+0t5W0m+Fje1jIt8rw==",
-      "requires": {
-        "graceful-fs": "^4.1.9"
-      }
-    },
     "levn": {
       "version": "0.3.0",
       "resolved": "https://registry.npmjs.org/levn/-/levn-0.3.0.tgz",

services/filestore/package.json

@@ -25,7 +25,6 @@
     "aws-sdk": "^2.628.0",
     "body-parser": "^1.2.0",
     "express": "^4.2.0",
-    "fs-extra": "^1.0.0",
     "glob": "^7.1.6",
     "heapdump": "^0.3.2",
     "logger-sharelatex": "^1.7.0",