Allow setting DATA_UPLOAD_MAX_NUMBER_FIELDS via env variables.
Allow setting DATA_UPLOAD_MAX_NUMBER_FIELDS via env variables.

Required for the migration to ASR snippets or
SuspiciousOperation (TooManyFields) will be raised due to the number of Snippets
selected in the admin tool.

mozmar/snippets-service,mozilla/snippets-service,mozmar/snippets-service,glogiotatidis/snippets-service,mozilla/snippets-service,mozmar/snippets-service,mozilla/snippets-service,mozmar/snippets-service,mozilla/snippets-service,glogiotatidis/snippets-service,glogiotatidis/snippets-service,glogiotatidis/snippets-service