Update file(s) from wp-cli/.github

Author: schlessera

.travis.yml

@@ -48,6 +48,9 @@ script:
 
 jobs:
   include:
+    - stage: test
+      php: nightly
+      env: WP_VERSION=trunk
     - stage: test
       php: 7.4
       env: WP_VERSION=latest
@@ -73,3 +76,8 @@ jobs:
     - stage: test
       php: 5.6
       env: WP_VERSION=trunk
+
+  allow_failures:
+    - stage: test
+      php: nightly
+      env: WP_VERSION=trunk