[AIRFLOW-7088] Avoid reading store_dag_code option in loop

[mik-laj]

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Issue link: AIRFLOW-7088

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• Description above provides context of the change
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[codecov-io]

Codecov Report

Merging #7764 into master will decrease coverage by 0.25%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #7764      +/-   ##
==========================================
- Coverage   86.93%   86.67%   -0.26%     
==========================================
  Files         920      920              
  Lines       44447    44448       +1     
==========================================
- Hits        38640    38526     -114     
- Misses       5807     5922     +115     

Impacted Files	Coverage Δ
airflow/utils/dag_processing.py	88.04% <100.00%> (+0.02%)	⬆️
airflow/kubernetes/volume_mount.py	44.44% <0.00%> (-55.56%)	⬇️
airflow/kubernetes/volume.py	52.94% <0.00%> (-47.06%)	⬇️
airflow/kubernetes/pod_launcher.py	47.18% <0.00%> (-45.08%)	⬇️
...viders/cncf/kubernetes/operators/kubernetes_pod.py	69.69% <0.00%> (-25.26%)	⬇️
airflow/kubernetes/refresh_config.py	50.98% <0.00%> (-23.53%)	⬇️
airflow/jobs/backfill_job.py	92.11% <0.00%> (+1.12%)	⬆️

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