Remove process.umask() call from config default

Since we now are using pacote/tar in a way that will rely on the default
process umask setting, and we set file/directory modes explicitly
anyway, there's no need to have a default umask setting that calls
process.umask()

As this method is not worker-thread safe, and is deprecated, it's best
for us to stop using it.

Fix: #1103

lib/utils/config.js

@@ -170,7 +170,7 @@ const defaults = {
   'tag-version-prefix': 'v',
   timing: false,
   tmp: tmpdir(),
-  umask: process.umask ? process.umask() : 0o22,
+  umask: 0,
   unicode,
   'update-notifier': true,
   usage: false,

tap-snapshots/test-lib-utils-config.js-TAP.test.js

@@ -131,7 +131,7 @@ Object {
     "tag-version-prefix": "v",
     "timing": false,
     "tmp": "/tmp",
-    "umask": 18,
+    "umask": 0,
     "unicode": true,
     "update-notifier": true,
     "usage": false,
@@ -658,7 +658,7 @@ Object {
     "tag-version-prefix": "v",
     "timing": false,
     "tmp": "/tmp",
-    "umask": 22,
+    "umask": 0,
     "unicode": true,
     "update-notifier": true,
     "usage": false,
@@ -1185,7 +1185,7 @@ Object {
     "tag-version-prefix": "v",
     "timing": false,
     "tmp": "/tmp",
-    "umask": 22,
+    "umask": 0,
     "unicode": true,
     "update-notifier": true,
     "usage": false,