fix pylint configuration

fix pylint configuration

- modify the method regex used:
  Tests methods name are commonly above the default limit of 32 char.
  They also use capital letters here to abide by the OpenROADM and WDM
  naming conventions.
- modify the variable regex used:
  It was supporting by default only the snake case and reported
  camel case variables as errors.
  Variable names also use capital letters here to abide by the OpenROADM
  and WDM naming conventions.
- disable the no-member check (inline):
  it reports many false positives since pylint is unable to retrieve
  the HTTP return codes given in the request package dictionary
- disable the too-many-public-methods check (inline):
  it reports many false positives since unittests requires many public
  methods

JIRA: TRNSPRTPCE-320
Signed-off-by: guillaume.lambert <guillaume.lambert@orange.com>
Change-Id: I21686442628591fd2c4af5182dc9f438e5701cb2