Need to improve sorting of node filter values

[Anastasia Palkina]

1. Create new environment by default
2. Add 4 controllers
3. Add label for each node:
- name = Mylabel value = 1
- name = Mylabel value = empty
- name = Mylabel value = test
- name = Mylabel value = a
4. Click "Filter nodes" button -> click 'More"-> choose "Mylabel"

Actual result: values for "Mylabel" is sorted randomly (see screen)

Expected result: need to improve sorting of filter's values. Values should be sorted alphabetically except special values like "Value is not specified" and "Label is not assigned", which should be highlighted somehow

VERSION:
  feature_groups:
    - mirantis
  production: "docker"
  release: "8.0"
  api: "1.0"
  build_number: "327"
  build_id: "327"
  fuel-nailgun_sha: "ec25ae8df28e1f1d87da653c5aab2711dff729f6"
  python-fuelclient_sha: "7c7a756fb6a3d091851c060003a2965c67aa353d"
  fuel-agent_sha: "d354cbe61b055db848a15ce66fb7ae92178d2c0a"
  fuel-nailgun-agent_sha: "a33a58d378c117c0f509b0e7badc6f0910364154"
  astute_sha: "c56dfde2da034151a7e707b381c4cf9d213b4ba2"
  fuel-library_sha: "bcc3d042a47547f6ad826360a85ef21dcaf25882"
  fuel-ostf_sha: "b2ebf15a3530b5c7b57707acf8642c1c3ac71bd8"
  fuel-mirror_sha: "8100acb3a566358d0d4ecc66de32d39626263028"
  fuelmenu_sha: "2942a85796d37f09ba8c8c6d762d8813292cf0d4"
  shotgun_sha: "cacb93cbc28910ff0dc38f30a855efa9af50d8ce"
  network-checker_sha: "d443ef47abeda58d319bc8d33d5005dd09440a02"
  fuel-upgrade_sha: "718aa3d7021fee2970f0fa6791cf5188578cc516"
  fuelmain_sha: "3faa824728ce60734abe602ff3778976f8a16eed"

[Bug Checker Bot (bug-checker)]

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