Glean v2 generated schemas

[BenWu]

Sample schema generator output for v2 schemas for https://mozilla-hub.atlassian.net/browse/DENG-8494.

Generated from mozilla/mozilla-schema-generator#302 with:

mozilla-schema-generator generate-glean-pings --out-dir schema_out/ --pretty --mps-branch benwu/remove-timing-dist-fields

for schema in $(find schema_out -name "*.schema.json" -type f); do
    bin/metadata_merge metadata/ "$schema"
done

find schema_out -type f -name "*.schema.json" | while read -r fname; do
    bq_out=${fname/schema.json/bq}
    mkdir -p "$(dirname "$bq_out")"
    jsonschema-transpiler \
        --resolve drop \
        --type bigquery \
        --normalize-case \
        --force-nullable \
        --tuple-struct \
            "$fname" > "$bq_out"
done

mozilla-schema-generator generate-glean-pings --out-dir schema_out/ --pretty --generic-schema --mps-branch benwu/remove-timing-dist-fields

#855 for the final changes to the v1 schemas