implement react-query for edge-cases (#1711)

When initially implementing react-query, we focussed on core features. This pull request now replaces the remaining apiClient usages in ui-components and ui-webapp with react-query hooks.

scm-ui/ui-api/src/index.ts

@@ -50,6 +50,9 @@ export * from "./import";
 export * from "./diff";
 export * from "./notifications";
 export * from "./configLink";
+export * from "./apiKeys";
+export * from "./publicKeys";
+export * from "./fileContent";
 export * from "./history";
 export * from "./contentType";
 export * from "./annotations";