chore: add release notes (#238)

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Signed-off-by: Frederic Wilhelm <frederic.wilhelm@sap.com>

Author: frewilhelm

docs/release_notes/v0.15.0.md

@@ -0,0 +1,19 @@
+# Release 0.15.0
+
+- chore(deps): bump github.com/fluxcd/cli-utils from 0.37.2-flux.1 to 1.0.0 (#237)
+- chore(deps): bump the go group with 5 updates (#236)
+- chore(deps): bump helm.sh/helm/v4 from 4.1.3 to 4.1.4 (#235)
+- chore(deps): bump go.opentelemetry.io/otel/sdk from 1.40.0 to 1.43.0 (#234)
+- chore(deps): bump github.com/aws/aws-sdk-go-v2/service/s3 from 1.96.4 to 1.99.0 (#233)
+- chore(deps): bump the go group across 1 directory with 9 updates (#230)
+- chore(deps): bump github.com/go-jose/go-jose/v4 from 4.1.3 to 4.1.4 (#232)
+- chore(deps): bump github.com/go-git/go-git/v5 from 5.16.5 to 5.17.1 (#231)
+- chore(deps): bump google.golang.org/grpc from 1.78.0 to 1.79.3 (#228)
+- chore(deps): bump the go group with 12 updates (#227)
+- chore(deps): bump sigs.k8s.io/controller-runtime from 0.23.1 to 0.23.3 in the go group (#225)
+- chore(deps): bump the go group with 11 updates (#223)
+- chore(deps): bump go.opentelemetry.io/otel/sdk from 1.38.0 to 1.40.0 (#224)
+- chore(deps): bump github.com/cloudflare/circl from 1.6.1 to 1.6.3 (#222)
+
+
+**Full Changelog**: https://github.com/open-component-model/ocm-e2e-framework/compare/v0.14.0...v0.15.0