Combine regulator tests into one executable

Combine the regulator tests into one executable to simplify running the
tests and maintaining the meson build files.

Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
Change-Id: I907a3d6ab5380eacef183d42e41f3b8e40735a99
diff --git a/phosphor-regulators/test/meson.build b/phosphor-regulators/test/meson.build
index ee880f0..6d6df82 100644
--- a/phosphor-regulators/test/meson.build
+++ b/phosphor-regulators/test/meson.build
@@ -3,12 +3,19 @@
     'actions'
 )
 
+phosphor_regulators_tests_source_files = [
+    'device_tests.cpp',
+    'id_map_tests.cpp',
+    'rail_tests.cpp',
+    'rule_tests.cpp',
+
+    'actions/action_environment_tests.cpp',
+    'actions/set_device_action_tests.cpp'
+]
+
 test('phosphor-regulators-tests',
      executable('phosphor-regulators-tests',
-                'device_tests.cpp',
-                'id_map_tests.cpp',
-                'rail_tests.cpp',
-                'rule_tests.cpp',
+                phosphor_regulators_tests_source_files,
                 dependencies: [
                     gmock,
                     gtest,
@@ -20,5 +27,3 @@
                 ]
      )
 )
-
-subdir('actions')