add Bioschemas annotation manually

[abotzki]

just realised that we need to manually enrich the annotation for Bioschemas in overrides/main.html

  {
    "@context": "https://schema.org/",
    "@type": "LearningResource",
    "@id": "https://elixir-europe-training.github.io/ELIXIR-TrP-LessonTemplate-MkDocs/",
    "http://purl.org/dc/terms/conformsTo": {
        "@type": "CreativeWork",
        "@id": "https://bioschemas.org/profiles/TrainingMaterial/1.0-RELEASE"
    },
    "description": "Template for ELIXIR lessons",
    "keywords": "FAIR, OPEN, Bioinformatics, Teaching",
    "name": "ELIXIR Training Lesson template",
    "license": "https://creativecommons.org/licenses/by/4.0/",
    "educationLevel": "beginner",
    "competencyRequired": "none",
    "teaches": "nothing yet to teach"
}