build: update qbittorrent to 5.2.0 and unstick prowlarr

prowlarr was pinned to a stale digest (v2.0.5.5160) via
.argocd-source-prowlarr.yaml; remove the file so the live app's
helm.parameters (which already has the current :latest digest =
v2.3.5.5327) takes effect.

qbittorrent: bump 5.1.0 -> 5.2.0.

custom_helm_charts/prowlarr/.argocd-source-prowlarr.yaml

@@ -1,8 +0,0 @@
-helm:
-  parameters:
-  - name: image.repository
-    value: lscr.io/linuxserver/prowlarr
-    forcestring: true
-  - name: image.tag
-    value: latest@sha256:4f2a6d597845b2f3e19284b1d982b3e0b4bd7c22472c2979c956aa198b83f472
-    forcestring: true

helm-values/qbittorrent_values.yaml

@@ -4,7 +4,7 @@ replicaCount: 1
 qbittorrent:
   image:
     repository: lscr.io/linuxserver/qbittorrent
-    tag: "5.1.0"
+    tag: "5.2.0"
     pullPolicy: Always
   env:
     - name: PUID