Add OMA courses held in Oulu and Leiden - #75

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Unexpected input(s) 'cache-dependency-path', valid inputs are ['cache', 'cache-version', 'extra-packages', 'needs', 'packages', 'pak-version', 'working-directory', 'dependencies', 'upgrade', 'lockfile-create-lib', 'install-pandoc', 'pandoc-version', 'install-quarto', 'quarto-version']

variable used before declaration

Unexpected input(s) 'cache-dependency-path', valid inputs are ['cache', 'cache-version', 'extra-packages', 'needs', 'packages', 'pak-version', 'working-directory', 'dependencies', 'upgrade', 'lockfile-create-lib', 'install-pandoc', 'pandoc-version', 'install-quarto', 'quarto-version']