Update curlimages/curl Docker tag to v8.15.0 (#3635)

| datasource | package         | from   | to     |
| ---------- | --------------- | ------ | ------ |
| docker     | curlimages/curl | 8.14.1 | 8.15.0 |

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

tests/suite/manifests/longevity/cronjob.yaml

@@ -40,7 +40,7 @@ spec:
           serviceAccountName: rollout-mgr
           containers:
           - name: coffee-rollout-mgr
-            image: curlimages/curl:8.14.1
+            image: curlimages/curl:8.15.0
             imagePullPolicy: IfNotPresent
             command:
             - /bin/sh
@@ -69,7 +69,7 @@ spec:
           serviceAccountName: rollout-mgr
           containers:
           - name: coffee-rollout-mgr
-            image: curlimages/curl:8.14.1
+            image: curlimages/curl:8.15.0
             imagePullPolicy: IfNotPresent
             command:
             - /bin/sh