Add missing headers to the changelog (jaegertracing#5179)

Signed-off-by: Yuri Shkuro <github@ysh.us>

CHANGELOG.md

@@ -24,6 +24,8 @@ run `make changelog` to generate content
 1.54.0 (2024-02-06)
 -------------------
 
+### Backend Changes
+
 #### ⛔ Breaking Changes:
 
 * Remove remnants of internal otlp types ([@yurishkuro](https://github.com/yurishkuro) in [#5107](https://github.com/jaegertracing/jaeger/pull/5107))
@@ -50,6 +52,8 @@ run `make changelog` to generate content
 1.53.0 (2024-01-08)
 -------------------
 
+### Backend Changes
+
 #### ⛔ Breaking Changes:
 
 * 💤 swap zipkin server for zipkin receiver from otel collector contrib ([@yurishkuro](https://github.com/yurishkuro) in [#5045](https://github.com/jaegertracing/jaeger/pull/5045))
@@ -87,6 +91,8 @@ run `make changelog` to generate content
 1.52.0 (2023-12-05)
 -------------------
 
+### Backend Changes
+
 #### ✨ New Features:
 
 * Support Elasticsearch 8.x ([@pmuls99](https://github.com/pmuls99) in [#4829](https://github.com/jaegertracing/jaeger/pull/4829))