lalpulsar: append to test_scripts and test_helpers

Description

The following warning was displayed from ./00boot:

test/python/Makefile.am:8: warning: test_scripts multiply defined in condition TRUE ...
gnuscripts/lalsuite_test.am:31: ... 'test_scripts' previously defined here
test/python/Makefile.am:2:   'gnuscripts/lalsuite_test.am' included from here
test/python/Makefile.am:16: warning: test_helpers multiply defined in condition TRUE ...
gnuscripts/lalsuite_test.am:32: ... 'test_helpers' previously defined here
test/python/Makefile.am:2:   'gnuscripts/lalsuite_test.am' included from here

this was due to the test_scripts and test_helpers variables not being appended to they were being defined multiple times. This patch updates Makefile.am to append to these variables instead of redefining them.

API Changes and Justification

Backwards Compatible Changes

• This change introduces no API changes
• This change adds new API calls

Backwards Incompatible Changes

• This change modifies an existing API
• This change removes an existing API

Review Status