throw at invalid profile name in shared ini file (#3585)

Author: AllanZhengYP

.changes/next-release/bugfix-Credentials-74d3274e.json

@@ -0,0 +1,5 @@
+{
+  "type": "bugfix",
+  "category": "Credentials",
+  "description": "SDK will throw if shared ini file's profile name can be resolved to __proto__"
+}

lib/util.js

@@ -219,6 +219,11 @@ var util = {
         var section = line.match(/^\s*\[([^\[\]]+)\]\s*$/);
         if (section) {
           currentSection = section[1];
+          if (currentSection === '__proto__' || currentSection.split(/\s/)[1] === '__proto__') {
+            throw util.error(
+              new Error('Cannot load profile name \'' + currentSection + '\' from shared ini file.')
+            );
+          }
         } else if (currentSection) {
           var item = line.match(/^\s*(.+?)\s*=\s*(.+?)\s*$/);
           if (item) {