samples: zephyrbt: Use YAML list syntax for twister tags

Upstream twister now rejects space-separated values in 'tags', raising a
ConfigurationError during test discovery:

  whitespace in 'tags' value 'zephyrbt lua' [...] Space-separated lists are not
  supported, write the value as a YAML list instead

This broke both the nightly CI and the main-next sync runs, which failed to load
the lua_conditions and robot_patrol suites. The remaining samples use single-word
tags and are unaffected.

Author: otavio

samples/subsys/zephyrbt/lua_conditions/sample.yaml

@@ -9,7 +9,9 @@ sample:
     behaviour tree nodes. Exercises _skipIf, _successIf,
     _failureIf, _onSuccess, _onFailure, and _post conditions.
 common:
-  tags: zephyrbt lua
+  tags:
+    - zephyrbt
+    - lua
 tests:
   samples.zephyrbt.lua_conditions:
     platform_allow:

samples/subsys/zephyrbt/robot_patrol/sample.yaml

@@ -11,7 +11,9 @@ sample:
     port aliasing, Lua pre/post conditions, and 4 user Lua
     override files. Features a live terminal UI animation.
 common:
-  tags: zephyrbt lua
+  tags:
+    - zephyrbt
+    - lua
 tests:
   samples.zephyrbt.robot_patrol:
     platform_allow: