refactor: Deflake and Try package

- feat: add CI multiplier
- refactor: readability
- feat: custom Sleep function
- refactor(integration): use custom Sleep
- feat: show Try progress
- feat(try): try response with status code
- refactor(try): use a dedicate package.
- refactor(integration): Try everywhere
- feat(CI): pass CI env var to Integration Tests.
- refactor(acme): increase timeout.
- feat(acme): show Traefik logs
- refactor(integration): use `http.StatusXXX`
- refactor: remove Sleep

integration/fixtures/https/clientca/https_2ca2config.toml

@@ -14,6 +14,9 @@ defaultEntryPoints = ["https"]
       CertFile = "fixtures/https/snitest.org.cert"
       KeyFile = "fixtures/https/snitest.org.key"
 
+[web]
+  address = ":8080"
+
 [file]
 
 [backends]