Attempting to append to a statically defined array, even if that array is empty or of compatible type, must produce an error at parse time.

[TyPR124]

Title is directly taken from https://github.com/toml-lang/toml#user-content-array-of-tables

As is this:

# INVALID TOML DOC
fruit = []

[[fruit]] # Not allowed

However this appears to parse as valid TOML.