[Dev Deps] update eslint, @ljharb/eslint-config, has-symbols; a…

…dd `safe-publish-latest`

package.json

@@ -9,6 +9,7 @@
 	"license": "MIT",
 	"main": "index.js",
 	"scripts": {
+		"prepublish": "safe-publish-latest",
 		"pretest": "npm run lint",
 		"tests-only": "node --harmony --es-staging test",
 		"test": "npm run tests-only",
@@ -32,16 +33,17 @@
 	],
 	"dependencies": {},
 	"devDependencies": {
-		"@ljharb/eslint-config": "^14.1.0",
+		"@ljharb/eslint-config": "^15.0.2",
 		"auto-changelog": "^1.16.2",
 		"covert": "^1.1.1",
 		"eclint": "^2.8.1",
-		"eslint": "^6.4.0",
+		"eslint": "^6.6.0",
 		"foreach": "^2.0.5",
-		"has-symbols": "^1.0.0",
+		"has-symbols": "^1.0.1",
 		"indexof": "^0.0.1",
 		"is": "^3.3.0",
 		"replace": "^1.1.1",
+		"safe-publish-latest": "^1.1.4",
 		"semver": "^6.3.0",
 		"tape": "^4.11.0"
 	},