fix: .gitignore to include memory tools

Added to .gitignore the following path, as it was
noticed as untracked after a TF-A CI run:
tools/memory/memory/__pycache__/

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: I35ba6f6a33593671c11f8e33c28545ae9bc57b4c
1 file changed