chore(feature-toggles): remove remnants of feature toggles (DEV-217) (#2176)

* remove remnants of feature toggles

* redo changes in PR template

* refactor admin list routes

* remove unused imports

* fix formatting

* refactor unnecessary companion objects in routes

* fix codacy issues

* fix codacy issues

* Update expected-client-test-data.txt

* add tests removed by accident

Co-authored-by: Ivan Subotic <400790+subotic@users.noreply.github.com>

Author: irinaschubert

docs/03-apis/api-v2/query-language.md

@@ -1201,8 +1201,6 @@ The query performance of triplestores, such as Fuseki, is highly dependent on th
 patterns. To improve performance, Gravsearch automatically reorders the
 statement patterns in the WHERE clause according to their dependencies on each other, to minimise
 the number of possible matches for each pattern.
-This optimization can be controlled using `gravsearch-dependency-optimisation` 
-[feature toggle](../feature-toggles.md), which is turned on by default.
 
 Consider the following Gravsearch query:
 

docs/03-apis/feature-toggles.md

@@ -15,5 +15,3 @@ The DSP APIs include:
   administering projects that use Knora as well as Knora itself.
 * The DSP [Util API](api-util/index.md), which is intended to be used for information retrieval
   about the DSP-stack itself.
-
-DSP API v2 and the admin API support [Feature Toggles](feature-toggles.md).

docs/03-apis/index.md

@@ -13,4 +13,3 @@
 - [Triplestore Updates](triplestore-updates.md)
 - [Consistency Checking](consistency-checking.md)
 - [Authentication](authentication.md)
-- [Feature Toggles](feature-toggles.md)

docs/05-internals/design/principles/feature-toggles.md

@@ -5,14 +5,9 @@
 
 # RDF Processing API
 
-Knora provides an API for parsing and formatting RDF data and
-for working with RDF graphs. This allows Knora developers to use a single,
+DSP provides an API for parsing and formatting RDF data and
+for working with RDF graphs. This allows DSP developers to use a single,
 idiomatic Scala API as a façade for a Java RDF library.
-By using a feature toggle, you can choose either
-[Jena](https://jena.apache.org/tutorials/rdf_api.html)
-or
-[RDF4J](https://rdf4j.org/documentation/programming/)
-as the underlying implementation.
 
 
 ## Overview
@@ -39,8 +34,8 @@ The API is in the package `org.knora.webapi.messages.util.rdf`. It includes:
 - `ShaclValidator`, which validates RDF models using SHACL shapes.
 
 To work with RDF models, start with `RdfFeatureFactory`, which returns instances
-of `RdfNodeFactory`, `RdfModelFactory`, `RdfFormatUtil`, and `ShaclValidator`,
-using feature toggle configuration. `JsonLDUtil` does not need a feature factory.
+of `RdfNodeFactory`, `RdfModelFactory`, `RdfFormatUtil`, and `ShaclValidator`. 
+`JsonLDUtil` does not need a feature factory.
 
 To iterate efficiently over the statements in an `RdfModel`, use its `iterator` method.
 An `RdfModel` cannot be modified while you are iterating over it.
@@ -93,20 +88,6 @@ Turtle file containing the graph of shapes.
 - The RDF4J-based implementation, in package `org.knora.webapi.messages.util.rdf.rdf4jimpl`.
 
 
-## Feature toggle
-
-For an overview of feature toggles, see [Feature Toggles](feature-toggles.md).
-
-The RDF API uses the feature toggle `jena-rdf-library`:
-
-- `on`: use the Jena implementation.
-
-- `off` (the default): use the RDF4J implementation.
-
-The default setting is used on startup, e.g. to read ontologies from the
-repository. After startup, the per-request setting is used.
-
-
 ## TODO
 
 - SHACL validation.