Pushgateway version bump
Pushgateway version bump

Upstream release:

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[CHANGE] Change of the storage format (necessary for the hash collision bugfix below). #293
[CHANGE] Check pushed metrics immediately and reject them if inconsistent. Successful pushes now result in code 200 (not 202). Failures result in code 400 and are logged at error level. #290
[FEATURE] Shutdown via HTTP request. Enable with --web.enable-lifecycle. #292
[FEATURE] Wipe storage completely via HTTP request and via web UI. Enable with --web.enable-admin-api. #287 #285
[BUGFIX] Rule out hash collisions between metric groups. #293
[BUGFIX] Avoid multiple calls of http.Error in push handler. #291
lest/prometheus-rpm,lest/prometheus-rpm