Cleanup the dev folder for v2-11-test branch (#61607)

We do not need some of the dev scripts in v2-11-test.

Author: potiuk

dev/README_RELEASE_AIRFLOW.md

@@ -675,7 +675,7 @@ Optionally it can be followed with constraints
 
 ```shell script
 pip install apache-airflow==<VERSION>rc<X> \
-  --constraint "https://raw.githubusercontent.com/apache/airflow/constraints-<VERSION>/constraints-3.9.txt"`
+  --constraint "https://raw.githubusercontent.com/apache/airflow/constraints-<VERSION>/constraints-3.10.txt"`
 ```
 
 Note that the constraints contain python version that you are installing it with.
@@ -687,15 +687,15 @@ There is also an easy way of installation with Breeze if you have the latest sou
 Running the following command will use tmux inside breeze, create `admin` user and run Webserver & Scheduler:
 
 ```shell script
-breeze start-airflow --use-airflow-version 2.7.0rc1 --python 3.9 --backend postgres
+breeze start-airflow --use-airflow-version 2.7.0rc1 --python 3.10 --backend postgres
 ```
 
 You can also choose different executors and extras to install when you are installing airflow this way. For
 example in order to run Airflow with CeleryExecutor and install celery, google and amazon provider (as of
 Airflow 2.7.0, you need to have celery provider installed to run Airflow with CeleryExecutor) you can run:
 
 ```shell script
-breeze start-airflow --use-airflow-version 2.7.0rc1 --python 3.9 --backend postgres \
+breeze start-airflow --use-airflow-version 2.7.0rc1 --python 3.10 --backend postgres \
   --executor CeleryExecutor --airflow-extras "celery,google,amazon"
 ```
 
@@ -831,7 +831,7 @@ the older branches, you should set the "skip" field to true.
 ## Verify production images
 
 ```shell script
-for PYTHON in 3.9 3.10 3.11 3.12
+for PYTHON in 3.10 3.11 3.12
 do
     docker pull apache/airflow:${VERSION}-python${PYTHON}
     breeze prod-image verify --image-name apache/airflow:${VERSION}-python${PYTHON}

dev/README_RELEASE_PROVIDER_PACKAGES.md

@@ -1016,7 +1016,7 @@ pip install apache-airflow-providers-<provider>==<VERSION>rc<X>
 ### Installing with Breeze
 
 ```shell
-breeze start-airflow --use-airflow-version 2.2.4 --python 3.9 --backend postgres \
+breeze start-airflow --use-airflow-version 2.2.4 --python 3.10 --backend postgres \
     --load-example-dags --load-default-connections
 ```