tests: add beautifulsoup4 dep to wato mypy target

test_host_diagnose.py imports bs4 for render-side coverage, so the
//tests/unit/cmk/gui/wato:wato target needs the beautifulsoup4
requirement to resolve its stubs under mypy.

Change-Id: Ic54bdbc80729c30751a67cad9d62141e61239605

Author: smeagol91

tests/unit/cmk/gui/wato/BUILD

@@ -24,6 +24,7 @@ py_test(
         "//cmk/gui/watolib:registries",
         "//tests/unit:conftest",
         "//tests/unit/cmk/gui:conftest",
+        requirement("beautifulsoup4"),
         requirement("flask"),
         requirement("pytest"),
         requirement("pytest-mock"),