Apply bind_executor explicitly.

[redboltz]

No description provided.

[codecov-commenter]

Codecov Report

Attention: 12 lines in your changes are missing coverage. Please review.

Comparison is base (a9d0326) 88.89% compared to head (290187b) 88.89%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #111      +/-   ##
==========================================
- Coverage   88.89%   88.89%   -0.01%     
==========================================
  Files          95       95              
  Lines       10256    10272      +16     
==========================================
+ Hits         9117     9131      +14     
- Misses       1139     1141       +2     

Files	Coverage Δ
include/async_mqtt/broker/endpoint_variant.hpp	98.33% <100.00%> (+0.01%)	⬆️
include/async_mqtt/endpoint.hpp	83.88% <100.00%> (+0.09%)	⬆️
include/async_mqtt/stream.hpp	82.05% <66.66%> (-0.21%)	⬇️