refactor(docker): use capital AS

[youtalk]

Description

I found the warnings below in the CI log. This PR just fixes them.

 4 warnings found (use --debug to expand):
 - FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 1)
 - FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 43)
 - FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 95)
 - FromAsCasing: 'as' and 'FROM' keywords' casing do not match (line 112)

Tests performed

Not applicable.

Effects on system behavior

Not applicable.

Interface changes

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