[bazel] Fix opentitan_select_top documentation

The docs for this function use non-existent top `english_breakfast` as
an example (`englishbreakfast` is the actual name). They also give an
example of using an array as a dictionary key, but arrays are
non-hashable and so a tuple must be used instead to make a collection
as a key.

Signed-off-by: Alex Jones <[email protected]>

Author: AlexJones0

hw/top/defs.bzl

@@ -66,7 +66,7 @@ def opentitan_select_top(values, default):
       name = "my_alias",
       actual = opentitan_select_top({
         "earlgrey": "//something:earlgrey",
-        ["english_breakfast", "darjeeling"]: "//something:else",
+        ("englishbreakfast", "darjeeling"): "//something:else",
       }, "//something:error")
     )
     """