Merge branch 'rich-syntax-highlighting' into 'master'

Use `rich` for syntax highlighting of `show_code` also in terminal

See merge request !139
8 jobs for release/0.2.9 in 9 minutes and 10 seconds (queued for 2 minutes and 55 seconds)
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Status Job ID Name Coverage
  Test
passed #346405
cuda docker
build-documentation

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passed #346404
cuda docker
flake8-lint

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passed #346401
docker
minimal-conda

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passed #346402
docker
minimal-sympy-master

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passed #346399
win
minimal-windows

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manual #346403
AVX cuda docker allowed to fail manual
pycodegen-integration
passed #346398
AVX cuda docker
tests-and-coverage

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77.03%
passed #346400
AVX cuda docker
ubuntu

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