Adding CUDA and OPENMP to LAMMPS experiment class

[august-knox]

Description

Adding CUDA and OPENMP to LAMMPS. Also added variant to enable/disable gtl.

Adding/modifying a benchmark (docs: Adding a Benchmark)

• (optional) If package upstreamed to Spack is insufficient, add/modify repo/benchmark_name/package.py
• (optional) If application upstreamed to Ramble is insufficient, add/modify repo/benchmark_name/application.py
• Tags in Ramble's application.py or in repo/benchmark_name/application.py will appear in the docs catalogue
• Add/modify an experiments/benchmark_name/experiment.py to define a single node and multi-node experiments
• Add/modify a dry run unit test in .github/workflows/run.yml