Rename `hw_mapping` to `instrument_cfg` in InstrumentCompiler and up

Description

Naming of the local variables referencing parts of the hardware configuration should be updated to instrument_cfg instead of hw_mapping

Motivation

The part of the hardware config that describes the instrument is more accurately named instrument_cfg, instead of hw_mapping which was the old name for hardware config

Example of where the renaming to instrument_cfg was already done:
https://gitlab.com/quantify-os/quantify-scheduler/blob/ef86d7ee445877e4d6c7a751778c359d74081f94/quantify_scheduler/backends/qblox/compiler_container.py#L92-110

Example of the old naming:
https://gitlab.com/quantify-os/quantify-scheduler/blob/ef86d7ee445877e4d6c7a751778c359d74081f94/quantify_scheduler/backends/qblox/compiler_abc.py#L88-108

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