Fix the failure of TestInputSocket.py when extra lines are found.

[bcoconni]

I had several occurrences in a row where the Ubuntu builds of the CI workflow are failing with the following error (note the empty string at the start of one list):

Lists differ: ['', 'get', 'help', 'hold', 'info', 'iterate', 'quit', 'resume', 'set'] != ['get', 'help', 'hold', 'info', 'iterate', 'quit', 'resume', 'set']

First differing element 0:
''
'get'

First list contains 1 additional elements.
First extra element 8:
'set'

- ['', 'get', 'help', 'hold', 'info', 'iterate', 'quit', 'resume', 'set']
?  ----

+ ['get', 'help', 'hold', 'info', 'iterate', 'quit', 'resume', 'set']
FAIL

I am not sure why Ubuntu is triggering this error while other platforms do not. And previously it was occurring seldomly while it is now happening systematically on the Ubuntu runners. This may be linked to the fact that CRLF are used in the help string while our Python code is splitting the lines using split("\n"):

jsbsim/src/input_output/FGInputSocket.cpp

Lines 255 to 264 in 3003423

	socket->Reply(
	" JSBSim Server commands:\r\n\r\n"
	" get {property name}\r\n"
	" set {property name} {value}\r\n"
	" hold\r\n"
	" resume\r\n"
	" iterate {value}\r\n"
	" help\r\n"
	" quit\r\n"
	" info\r\n\r\n");

jsbsim/tests/TestInputSocket.py

Lines 205 to 213 in 3003423

	out = await self.telnet.send_command("help")
	# Check that "help" returns the minimum set of commands that will be
	# tested
	self.assertEqual(
	sorted(
	map(
	lambda x: x.split("{")[0].strip(),
	out.split("\n")[2:-1],

This PR is replacing all occurrences of .split("\n") by .splitlines(). The latter handles correctly the various ends of lines (\n, \r\n, etc.). Following this change, the error stopped to occur on my fork.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 25.29%. Comparing base (3003423) to head (b35ec89).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1392   +/-   ##
=======================================
  Coverage   25.29%   25.29%           
=======================================
  Files         169      169           
  Lines       18570    18570           
=======================================
  Hits         4697     4697           
  Misses      13873    13873           

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[bcoconni]

The bug has been inadvertently demonstrated by the PR #1393.

[seanmcleod70]

Looks good.