Update knownBroken version (#165)

PR-URL: #165
Credit: @ljharb
Reviewed-By: @zkat
Reviewed-By: @aeschright

Author: ljharb

lib/utils/unsupported.js

@@ -8,7 +8,7 @@ var supportedNode = [
   {ver: '11', min: '11.0.0'},
   {ver: '12', min: '12.0.0'}
 ]
-var knownBroken = '<4.7.0'
+var knownBroken = '<6.0.0'
 
 var checkVersion = exports.checkVersion = function (version) {
   var versionNoPrerelease = version.replace(/-.*$/, '')

test/tap/unsupported.js

@@ -21,8 +21,8 @@ var versions = [
   ['v2.3.1', true, true],
   ['v3.0.0', true, true],
   ['v4.5.0', true, true],
-  ['v4.8.4', false, true],
-  ['v5.7.1', false, true],
+  ['v4.8.4', true, true],
+  ['v5.7.1', true, true],
   ['v6.8.1', false, false],
   ['v7.0.0-beta23', false, true],
   ['v7.2.3', false, true],