[BUG] Apalache fails with an unreadable message when Seq is used

[konnov]

This is a follow up of #957.

The specification mentioned there fails because of using Seq(S). We should improve the error message and guide the user to an explanation in the manual.

An MWE:

------------------------------- MODULE Bug1126 --------------------------------
\* an MWE for #1126

EXTENDS Sequences

VARIABLE
    \* @type: Seq(Int);
    seq

Init ==
    seq = << >>

Next ==
    \* as apalache does not support Seq(S), it fails here
    \E s \in Seq({1, 2, 3}):
        seq' = s
===============================================================================

[konnov]

The right way to fix it is by fixing #1127 first