fix link to scpi99.pdf

Description

SCPI moved the manual, breaking the pipeline for documentation

update links for the scpi-99 manual:

from

• https://www.ivifoundation.org/docs/scpi-99.pdf

to

• https://www.ivifoundation.org/downloads/SCPI/scpi-99.pdf

Type

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Code refactoring (only refactoring of existing code, without new functionality)

Issue(s)

Related MRs

https://gitlab.com/qblox/packages/software/qblox_instruments_docs/-/merge_requests/286

Testing

Notes

Only update the link in docstrings, no code changes

Merge checklist

• Cleaned up code (correct alligment/spacing/code-style, no dead code, etc).
• Merge request targets development branch.
• Assigned assignee (you) and reviewers (team-members).
• Merge request has been reviewed by at least one team-members.
• All pipelines pass, including manually triggered ones.
• If merging a repository with a release package, updated appropriate CHANGELOG.md:
  - PULSAR_QxM, CLUSTER_MM, QBLOX_INSTRUMENTS: file in same repository
  - CLSUTER_QxM: file in CLUSTER_MM repo