Add institution: MTU

[github-actions]

This pull request was automatically created by a GitHub Actions workflow.

Data submitted by @wolfiex

Adding the following new data.

{
    "@id": "mip-cmor-tables:organisations/institutions/mtu",
    "@type": "institution",
    "acronyms": [
        "MTU"
    ],
    "aliases": [
        "Michigan Tech"
    ],
    "cmip_acronym": "MTU",
    "established": 1885,
    "kind": "Education",
    "labels": [],
    "location": {
        "@id": "mip-cmor-tables:organisations/institutions/location/0036rpn28",
        "@type": "location",
        "@nest": {
            "lat": 47.12,
            "lon": 47.12,
            "city": "Houghton",
            "country": [
                "United States",
                "US"
            ]
        }
    },
    "name": "Michigan Technological University",
    "ror": "0036rpn28",
    "url": [
        "http://www.mtu.edu/"
    ]
}

Resolves #73

[durack1]

Do we have a request to register this institution_id - #73 doesn't seem to have an external requestor