ETags on static data endpoints

[CarbonAlabel]

Currently, all static data endpoints are returning weak ETags, and as requested in #364, the returned ETag is based off the server version.

This makes the ETag almost useless when it comes to reusing old responses, as updates typically only make a few changes to the static data (or none at all), but the new ETag will indicate that all of the static data has changed, making ESI retransmit the data.

I'm requesting that the static data endpoints be updated to use strong ETags, which will enable them to only send the response if the requested static data has actually been changed.

[CarbonAlabel]

Conversation snippets from Tweetfleet Slack, April 23rd (times CEST):

CCP Bartender [15:30]
[referring to this issue] that's a really large task to solve. I'm aware of it but it's not likely to receive any attention any time soon.

Carbon Alabel [15:51]
Was kinda hoping it would be a quick change.

CCP Bartender [16:04]
nah, snowedin talked about it a lot but I know it was a big change