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
 
@@ -147,6 +147,6 @@ depends_on:
 
 ---
 kind: signature
-hmac: e651aac1eea6516a843c412b82cb80775f06de9b0888fc43d2e91ef9b9d9cfb8
+hmac: f5ed46b889edd3e7fca7737890a3342e82015946a23709ef7cd680992ca4e8ff
 
 ...