Update VSCode interactive node setup for current IRB cluster #325

Problem

The VSCode in interactive node page (docs/Tools/VSCode/cluster_node.md) contains outdated and redundant steps that no longer apply after the migration to the new IRB cluster (CPD).

Changes needed

• Remove Step 3 (manual SSH tunnel) — obsolete now that the SSH config uses ProxyJump + Port 2222
• Update login node hostname from irblogin01.irbbarcelona.pcb.ub.es to irblogin02.sc.irbbarcelona.org
• Simplify the helper function to remove the obsolete tunnel-creation logic
• Update the hostname example to the current .sc.irbbarcelona.org domain
• Fix misleading #SBATCH directives in vscode-interactive-job.sh (run with bash, not sbatch)
• Renumber steps after deletion

Context

Supersedes #292, which covered the same topic but was closed without resolution.