fix(zjow): fix bugs in dmc2gym env.

[zjowowen]

1, fix the observation dimension error of dmc env "cartpole".
2, fix the observation data type error when it is observed in pixel.
3, try to fix the not response problem when mujoco opengl render, under the condition that the dmc env is both initiated in main thread and subprocess thread.

[codecov]

Codecov Report

Merging #391 (bdb34b4) into main (47940ef) will increase coverage by 0.15%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##             main     #391      +/-   ##
==========================================
+ Coverage   85.87%   86.03%   +0.15%     
==========================================
  Files         522      522              
  Lines       40835    41234     +399     
==========================================
+ Hits        35069    35474     +405     
+ Misses       5766     5760       -6     

Flag	Coverage Δ
unittests	86.03% <50.00%> (+0.15%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
ding/utils/render_helper.py	25.00% <0.00%> (-4.42%)	⬇️
ding/envs/env_manager/base_env_manager.py	90.37% <100.00%> (+0.29%)	⬆️
ding/framework/event_loop.py	92.98% <0.00%> (-3.51%)	⬇️
ding/interaction/tests/test_utils/stream.py	75.00% <0.00%> (-2.78%)	⬇️
ding/interaction/base/network.py	96.34% <0.00%> (-1.25%)	⬇️
ding/framework/parallel.py	85.18% <0.00%> (-1.14%)	⬇️
ding/envs/env_manager/subprocess_env_manager.py	76.78% <0.00%> (-0.65%)	⬇️
ding/framework/middleware/collector.py	87.03% <0.00%> (-0.47%)	⬇️
...worker/replay_buffer/tests/test_advanced_buffer.py	97.80% <0.00%> (-0.44%)	⬇️
ding/worker/replay_buffer/advanced_buffer.py	92.77% <0.00%> (-0.32%)	⬇️
... and 219 more

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