remove dependency on etn in sql file calls

[PietrH]

In a number of places etnservice calls files from etn, this is unwanted behaviour, these files have now been copied over to etnservice and references should be made relative to included files instead of an external dependency instead.

example

  project_sql <- glue::glue_sql(
    readr::read_file(system.file("sql", "project.sql", package = "etn")),
    .con = connection
  )