Release v1.3.0 (#167)

* Update changelog for v1.3.0 release

* Apply suggestions from code review

Co-authored-by: Robert Pająk <rpajak@splunk.com>

* Update CHANGELOG.md

* Update CHANGELOG.md

* Update CHANGELOG.md

Co-authored-by: Robert Pająk <rpajak@splunk.com>

* Update CHANGELOG.md

Co-authored-by: Robert Pająk <rpajak@splunk.com>

CHANGELOG.md

@@ -2,16 +2,51 @@
 
 ## [Unreleased]
 
+## [1.3.0] - 2022-05-19
+
 ### General
 
 - Add support information into versioning specification.
+- Add behaviors specification.
 - Refactor profiling into existing specification structure.
 
 #### Bug fixes
 
 - Replaced the example for Java system properties in `specification/configuration.md`.
 - Increase profiling rate from 1s to 10s.
 
+### Configuration
+
+#### Breaking Changes
+
+- Change the Kubernetes package management solutions configuration option
+  default for `splunkPlatform.metricsEnabled` to be `false`.
+
+#### Enhancements
+
+- Add `SPLUNK_REALM` to required environment variables that need to be
+  supported by instrumentation libraries.
+- Add `SPLUNK_PROFILER*` environment variables
+  (`SPLUNK_PROFILER_CALL_STACK_INTERVAL`, `SPLUNK_PROFILER_ENABLED`,
+  `SPLUNK_PROFILER_LOGS_ENDPOINT`) to the required configuration for
+  instrumentation libraries.
+- Add `OTEL_TRACES_EXPORTER` to required environment variables that need to be
+  supported by serverless instrumentation libraries.
+
+### Semantic Conventions
+
+#### Breaking Changes
+
+- Use `os.name` instead of `os.type` for mobile RUM libraries.
+
+#### Bugfixes
+
+- Correct stability guarantee of the RUM section as experimental.
+
+#### Enhancements
+
+- Add experimental profiling semantic conventions.
+
 ## [1.2.0] - 2021-11-15
 
 ### General
@@ -122,7 +157,8 @@
 - Primary focus is on Instrumentation Libraries for initial 1.0 release
 - Initial Collector specification defined
 
-[Unreleased]: https://github.com/signalfx/gdi-specification/compare/v1.2.0...HEAD
+[Unreleased]: https://github.com/signalfx/gdi-specification/compare/v1.3.0...HEAD
+[1.3.0]: https://github.com/signalfx/gdi-specification/releases/tag/v1.3.0
 [1.2.0]: https://github.com/signalfx/gdi-specification/releases/tag/v1.2.0
 [1.1.0]: https://github.com/signalfx/gdi-specification/releases/tag/v1.1.0
 [1.0.0]: https://github.com/signalfx/gdi-specification/releases/tag/v1.0.0