Update changelog with v1.2.0 (#1143)

CHANGELOG.md

@@ -7,7 +7,7 @@ This document contains a historical list of changes between releases. Only
 changes that impact end-user behavior are listed; changes to documentation or
 internal API changes are not present.
 
-v1.2.0-rc.1
+v1.2.0
 -----------------
 
 ### Security fixes
@@ -16,9 +16,6 @@ v1.2.0-rc.1
   - [CVE-2024-35255](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-35255)
   - [CVE-2024-36129](https://avd.aquasec.com/nvd/2024/cve-2024-36129/)
 
-v1.2.0-rc.0
------------------
-
 ### Breaking changes
 
 - Updated OpenTelemetry to v0.102.1. (@mattdurham)