add meson support, update pipeline

test/meson.build

@@ -0,0 +1,18 @@
+test_sources = files([
+      'test_main.cpp',
+      'test_converter.cpp',
+      'test_parser.cpp',
+      'test_extractions.cpp',
+      ])
+
+doctest_proj = subproject('doctest')
+doctest_dep = doctest_proj.get_variable('doctest_dep')
+
+test_exe = executable('test_ssp', 
+  sources: test_sources, 
+  dependencies: doctest_dep, 
+  include_directories: includes,
+  cpp_args: '-lstdc++fs'
+  )
+
+test('tests_ssp', test_exe)