Fixing Illegal Byte Sequence

[otaviof]

Changes

Small pull-request to avoid possible errors reading /dev/urandom with tr. As in:

$ tr -dc a-z < /dev/urandom
tr: Illegal byte sequence

Submitter Checklist

• Includes tests if functionality changed/was added
• Includes docs if changes are user-facing
• Set a kind label on this PR
• Release notes block has been filled in, or marked NONE

Release Notes

NONE

[otaviof]

/assign @akram
/assign @coreydaley

[openshift-ci]

@otaviof: GitHub didn't allow me to assign the following users: akram.

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In response to this:

/assign @akram
/assign @coreydaley

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[gabemontero]

/approve
/lgtm

[openshift-ci]

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