Harmonize http status code usage

[jianglai]

Given that we run servlets, it makes sense to always use the status
code contants from the servlet class.

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This change is 

[jianglai]

Reviewed 28 of 28 files at r1, all commit messages.
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[gbrodman]

Reviewed 27 of 28 files at r1, 1 of 1 files at r2, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @jianglai)

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core/src/main/java/google/registry/ui/server/console/ConsoleApiAction.java line 17 at r2 (raw file):

package google.registry.ui.server.console;

import static com.github.dockerjava.zerodep.shaded.org.apache.hc.core5.http.HttpStatus.SC_INTERNAL_SERVER_ERROR;

hisssssss

should we have a presubmit banning import .*[.]shaded[.].*; ?

[jianglai]

Reviewed 2 of 2 files at r3, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @gbrodman)

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core/src/main/java/google/registry/ui/server/console/ConsoleApiAction.java line 17 at r2 (raw file):

Previously, gbrodman wrote…

hisssssss

should we have a presubmit banning import .*[.]shaded[.].*; ?

Good catch, I actually added several presubmit regarding various shaded dependencies:

https://cs.opensource.google/nomulus/nomulus/+/master:config/presubmits.py;l=176?q=presubmit&ss=nomulus%2Fnomulus

I guess if import .*[.]shaded[.].* is not too aggressive, we can use it.

[gbrodman]

Reviewed 2 of 2 files at r3, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @jianglai)