Add validation for malformed interface ranges

[bgallagher-nexthop]

Fixes #4574.

What I did

It is possible to run sudo config interface startup Ethernet320-Ethernet376 or sudo config interface shutdown Ethernet320-Ethernet376 and the command will return silently without actually having done anything because the valid format for a range specifier is Ethernet320-376.

This PR adds validation to these CLI commands so that malformed range specifiers will cause the CLI to print an error message.

How I did it

I added logic to raise an exception when a malformed range specifier is provided by the user to the CLI.

How to verify it

Added unit-tests, manually tested below.

Previous command output (if the output of a command-line utility has changed)

Before the change:

admin@device:~$ show int stat Ethernet0-8
  Interface                   Lanes    Speed    MTU    FEC    Alias    Vlan    Oper    Admin    Type    Asym PFC
-----------  ----------------------  -------  -----  -----  -------  ------  ------  -------  ------  ----------
  Ethernet0  9,10,11,12,13,14,15,16     800G   9100     rs    Port1  routed    down       up     N/A         N/A
  Ethernet8         1,2,3,4,5,6,7,8     800G   9100     rs    Port2  routed    down       up     N/A         N/A
admin@device:~$ sudo config interface shutdown Ethernet0-Ethernet8
admin@device:~$ show int stat Ethernet0-8
  Interface                   Lanes    Speed    MTU    FEC    Alias    Vlan    Oper    Admin    Type    Asym PFC
-----------  ----------------------  -------  -----  -----  -------  ------  ------  -------  ------  ----------
  Ethernet0  9,10,11,12,13,14,15,16     800G   9100     rs    Port1  routed    down       up     N/A         N/A
  Ethernet8         1,2,3,4,5,6,7,8     800G   9100     rs    Port2  routed    down       up     N/A         N/A

New command output (if the output of a command-line utility has changed)

After the change:

admin@device:~$ sudo config interface shutdown Ethernet0-Ethernet8
Usage: config interface shutdown [OPTIONS] <interface_name>
Try 'config interface shutdown -h' for help.

Error: Invalid interface range 'Ethernet0-Ethernet8'. Expected a range like 'Ethernet0-3'.
admin@device:~$ sudo config interface startup Ethernet0-Ethernet8
Usage: config interface startup [OPTIONS] <interface_name>
Try 'config interface startup -h' for help.

Error: Invalid interface range 'Ethernet0-Ethernet8'. Expected a range like 'Ethernet0-3'.

[mssonicbld]

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[mssonicbld]

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