update CHANGELOG and bump version to 5.4.2

Author: basepi

CHANGELOG.asciidoc

@@ -26,6 +26,16 @@ endif::[]
 [[release-notes-5.x]]
 === Python Agent version 5.x
 
+[[release-notes-5.4.2]]
+==== v5.4.2
+
+https://github.com/elastic/apm-agent-python/compare/v5.4.1\...v5.4.2[Check the diff]
+
+[float]
+===== Bug fixes
+
+ * fixed a bug in our celery implementation related to the threading refactor in 5.4.0 {pull}724[#724]
+
 [[release-notes-5.4.1]]
 ==== v5.4.1
 

elasticapm/version.py

@@ -28,5 +28,5 @@
 #  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 #  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-__version__ = (5, 4, 1)
+__version__ = (5, 4, 2)
 VERSION = ".".join(map(str, __version__))