build(deps): bump idna from 3.11 to 3.15 in ContentProcessorAPI

Applies the changes from Dependabot PR #595 onto dev so they reach the dev branch ahead of the upstream PR (which targets main).

Refs: ADO #44960

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: Shreyas-Microsoft

src/ContentProcessorAPI/requirements.txt

@@ -22,7 +22,7 @@ h11==0.16.0
 httpcore==1.0.9
 httptools==0.7.1
 httpx==0.28.1
-idna==3.11
+idna==3.15
 isodate==0.7.2
 jinja2==3.1.6
 jsonschema==4.25.1