fix ci yapf command if no python files found

.drone.jsonnet

@@ -21,7 +21,7 @@ local PipelineLinting = {
       },
       commands: [
         'pip install -qq yapf',
-        '[ ! -z "$(find .  -type f -name *.py)" ] && yapf -rd ./',
+        '[ -z "$(find .  -type f -name *.py)" ] || (yapf -rd ./)',
       ],
     },
     {

.drone.yml

@@ -16,7 +16,7 @@ steps:
   image: python:3.9
   commands:
   - pip install -qq yapf
-  - "[ ! -z \"$(find .  -type f -name *.py)\" ] && yapf -rd ./"
+  - "[ -z \"$(find .  -type f -name *.py)\" ] || (yapf -rd ./)"
   environment:
     PY_COLORS: 1
 
@@ -115,6 +115,6 @@ depends_on:
 
 ---
 kind: signature
-hmac: c99168e58d387239b411096b69ec2b98af22fa2565715ba1f2cafe45152c2b3c
+hmac: 9a0f08c0af83b70cbdc16356e59fb7b350980858103ddfbc62917bdd9404d641
 
 ...