chore: Rename staging servers to stage in Makefile

[seakayone]

Pull Request Checklist

Task Description/Number

Issue Number: DEV-

PR Type

• build/chore: maintenance tasks (no production code change)
• docs: documentation changes (no production code change)
• feat: represents new features
• fix: represents bug fixes
• perf: performance improvements
• refactor: represents production code refactoring
• test: adding or refactoring tests (no production code change)

Basic requirements for bug fixes and features

• Tests for the changes have been added
• Docs have been added / updated

Does this PR introduce a breaking change?

• Yes

Does this PR change client-test-data?

• Yes

[codecov]

Codecov Report

Attention: 65 lines in your changes are missing coverage. Please review.

Comparison is base (44e6bdc) 11.63% compared to head (1158a36) 88.52%.
Report is 10 commits behind head on main.

Files	Patch %	Lines
...knora/webapi/messages/util/rdf/RdfFormatUtil.scala	84.41%	12 Missing ⚠️
...c/main/scala/org/knora/webapi/OntologySchema.scala	58.33%	10 Missing ⚠️
...cala/org/knora/webapi/slice/common/api/ApiV2.scala	82.60%	8 Missing ⚠️
...nora/webapi/slice/search/api/SearchEndpoints.scala	89.33%	8 Missing ⚠️
...n/scala/org/knora/webapi/routing/RouteUtilV2.scala	70.58%	5 Missing ⚠️
.../knora/webapi/slice/common/api/BaseEndpoints.scala	70.58%	5 Missing ⚠️
...org/knora/webapi/messages/util/rdf/JenaModel.scala	87.50%	3 Missing ⚠️
...knora/webapi/responders/v2/SearchResponderV2.scala	93.87%	3 Missing ⚠️
.../store/triplestore/upgrade/RepositoryUpdater.scala	0.00%	3 Missing ⚠️
webapi/src/main/scala/dsp/valueobjects/Iri.scala	0.00%	2 Missing ⚠️
... and 4 more

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #2961       +/-   ##
===========================================
+ Coverage   11.63%   88.52%   +76.89%     
===========================================
  Files         246      246               
  Lines       22880    22870       -10     
===========================================
+ Hits         2661    20245    +17584     
+ Misses      20219     2625    -17594     

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