guix: remove test-security/symbol-check scripts

Summary:
These scripts are becoming more of nuisance, than a value-add;
particularly since we've been building releases using Guix. Adding new
(release bin) tests can be harder, because it requires constructing a
failing test, which is becoming less easy e.g trying to disable a
feature or protection that has been built into the compiler/toolchain by
default.

In the pre-Guix days, these were valuable to sanity-check the environment,
because we were pulling that pre-built from Ubuntu, with little control.
At this point, it's less clear what these scripts are (sanity) checking.

This is a backport of core#31818

Test Plan: I will run guix builds in a dependency of this diff just to confirm that these scripts are currently unused.

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Subscribers: Fabien

Differential Revision: https://reviews.bitcoinabc.org/D18898