Remove Database.CleartextPassword from the data model

There's no reason for it to be exposed, it is currently an
implementation detail in how new MySQL databases are created (the
password reset flow for databases does not use it after that).
4 jobs for master in 4 minutes and 42 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build Pkgsrc
passed #9208
build_pkgsrc:stretch

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  Build Pkg
passed #9209
amd64
build_pkg:stretch:amd64

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passed #9210
arm64
build_pkg:stretch:arm64

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  Upload Pkg
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upload_pkg

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