build(test): restrict gdb-15 install to amd64 architecture

[dmehala]

Description

PR #71 updates gdb to a newer version that supports reading DWARF debugging format. However, it incorrectly attempts to install the x86_64 version regardless of the system's architecture, causing errors on non-x86_64 platforms.

This fix temporarily ensures that the updated gdb is only installed on x86_64 (amd64) systems.

Note to reviewers

This is blocking the new release.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.22%. Comparing base (9c9837c) to head (ef4c733).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #114   +/-   ##
=======================================
  Coverage   77.22%   77.22%           
=======================================
  Files          36       36           
  Lines        4000     4000           
  Branches      671      671           
=======================================
  Hits         3089     3089           
  Misses        875      875           
  Partials       36       36           

[dubloom]

It seems that we don't want to do anything on non amd64 system, do you know why ?

[dmehala]

@dubloom gdb is installed for all architecture, but gdb-15 will not be installed for ubuntu on arm64 architecture for the following reasons:

1. It is currently blocking the release, so this serves as more of a workaround.
2. gdb is not mandatory for testing purpose, so this workaround should be effective.
3. The resources to build and package gdb15 for ubuntu arm64 are unfortunately unavailable at this time.
4. It's likely that the versions requiring a gdb upgrade will no longer be supported after this release.