Remove enviroment variables for debug assertions (reverts #480)

This reverts commit 97d8768. Follow up
to #14025 servo issue. Adds linux-rel-wpt and linux-rel-css in place of
linux-rel

buildbot/master/files/config/environments.py

@@ -77,10 +77,6 @@ def without(self, to_unset):
     'SHELL': '/bin/bash',
 })
 
-build_linux_rel_debug_assert = build_linux + Environment({
-    'SERVO_ENABLE_DEBUG_ASSERTIONS': '1',
-})
-
 build_android = build_linux + Environment({
     'ANDROID_NDK': '{{ common.servo_home }}/android/ndk/current/',
     'ANDROID_SDK': '{{ common.servo_home }}/android/sdk/current/',

buildbot/master/files/config/master.cfg

@@ -157,10 +157,8 @@ c['builders'] = [
     DynamicServoBuilder("arm64", CROSS_SLAVES, envs.build_arm64),
     DynamicServoBuilder("linux-dev", LINUX_SLAVES, envs.build_linux),
     DynamicServoBuilder("linux-nightly", LINUX_SLAVES, envs.build_linux),
-    DynamicServoBuilder("linux-rel-css", LINUX_SLAVES,
-                        envs.build_linux_rel_debug_assert),
-    DynamicServoBuilder("linux-rel-wpt", LINUX_SLAVES,
-                        envs.build_linux_rel_debug_assert),
+    DynamicServoBuilder("linux-rel-wpt", LINUX_SLAVES, envs.build_linux),
+    DynamicServoBuilder("linux-rel-css", LINUX_SLAVES, envs.build_linux),
     DynamicServoBuilder("linux-rel-intermittent", LINUX_SLAVES,
                         envs.build_linux),
     DynamicServoBuilder("mac-dev-unit", MAC_SLAVES, envs.build_mac),