Local network shows incorrect name

[jefflau]

Describe the bug

Sometimes when I have many custom RPC endpoints on Metamask, when I go back to the private network, it shows the incorrect name (usually one of my custom endpoint names)

To Reproduce
Create a custom RPC endpoint (or many custom RPC endpoints). Start to use a local private ganache node and choose the private network in Metamask. Check the name of the network.
Expected behavior

Private network shows the private network name, not the custom endpoint name

Screenshots

Browser details (please complete the following information):

• OS: OSX
• Browser Chrome
• MetaMask Version 6.3.1

[tmashuang]

Closing as a duplicate of #6321