Fix installation script

[rmedina97]

Hi!

With this PR, I refactored the installation guides by removing the old one and integrating its relevant parts into the current documentation.

Changes:

1. tools/script/requirements.sh

   • Fixed liqoctl installation by removing the logic for unstable versions.
   • Created the checks_kind function and added it to checks_tools.
   • Added automatic Docker installation.
   • Pinned tool versions: kubectl (v1.33), kind (v0.27), and Docker (stable).

2. Removed the testbed folder (previous location of the old guide):

   • The consumer, provider, and metric server yaml files were already available in the quickstart folder, which are the ones referenced by the new guide.

3. docs/installation/installation.md

   • Added content from the old guide under the "Testbed Installation" section.
   • Introduced new sections: Prerequisites, Common issues with kind, and Usage.
   • In the Manual Installation section, fixed:
     • Link to Liqo,
     • Path to consumer-values.yaml,
     • Added description of the install_liqo.sh usage.

4. tools/script/install_liqo.sh

   • Added parameter checks.

5. tools/script/environment.sh

   • Removed architecture-specific dependencies in the Macvlan plugin installation link.

Thanks in advance for your feedback!

[LorenzoMoro]

LGTM

[LorenzoMoro]

See note