update CHANGELOG and bump version to 5.3.3

Author: beniwohli

CHANGELOG.asciidoc

@@ -30,6 +30,17 @@ https://github.com/elastic/apm-agent-python/compare/v5.3.1\...master[Check the d
 [[release-notes-5.x]]
 === Python Agent version 5.x
 
+[[release-notes-5.3.3]]
+==== v5.3.3
+
+https://github.com/elastic/apm-agent-python/compare/v5.3.2\...v5.3.3[Check the diff]
+
+[float]
+===== Bug fixes
+
+ * Fixed an issue with OpenTracing bridge and dropped spans {pull}687[#687]
+ * Fixed bug that would make the agent ignore the `hostname` configuration setting {pull}689[#689]
+
 [[release-notes-5.3.2]]
 ==== v5.3.2
 

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, 3, 2)
+__version__ = (5, 3, 3)
 VERSION = ".".join(map(str, __version__))