fix(connection): unpack_from error caused by network issues

Description

add error msg for timeout + network config issues
add integration tests for error
add unit tests for error

Motivation and Context

Problem: When the server side socket closes due to the network issues, redshift-connector raises an unpack_from error that is confusing and misleading to users. Now, when the server side socket closes due to network issues, redshift-connector will raise the error suggesting users to double check their client-side networking configurations, and if they set a timeout for their connection, will ask them to raise it or use None as default.

The fix address this issue. (due to network issues)

Testing

Wrote unit and integration tests. Ran manual tests using default timeout and manually setting timeout:

Deterministic example:

conn = redshift_connector.connect(dbkwargs)
conn2 = redshift_connector.connect(dbkwargs)
res = conn2.run("select pg_backend_pid()")
pid1 = res[0][0]

conn.run("select pg_terminate_backend(:v)", v=pid1)
conn2.run("select 1")

Nondeterministic example:

conn = redshift_connector.connect(dbkwargs)
cursor = conn.cursor()
try:
   for i in range(100):
      print(f"Connection is open. Waiting... {i} round")
      time.sleep(33)
      cursor.execute("select * from svv_all_columns")
     time.sleep(17)

except Exception as e:
   raise e
finally:
   cursor.close()

Screenshots (if appropriate)

Types of changes

[x] Bug fix (non-breaking change which fixes an issue)
[ ] New feature (non-breaking change which adds functionality)

Checklist

[x] Local run of ./build.sh succeeds
[x] Code changes have been run against the repository's pre-commit hooks
[x] Commit messages follow Conventional Commit Specification
[x] I have read the README document
[x] I have added tests to cover my changes
[x] I have run all unit tests using pytest test/unit and they are passing.
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aws / amazon-redshift-python-driver