style: ruff format and the lint rules of the driver standard

Mechanical: ruff format, and ruff check --fix with the rule set every NAPALM
driver uses (E, F, I, UP, B at line length 100, Python 3.10). What ruff
cannot fix comes in the next commit.

README.md

@@ -74,10 +74,12 @@ Configuration is managed via [UCI](https://openwrt.org/docs/guide-user/base-syst
 ### Merge candidate
 
 ```python
-device.load_merge_candidate(config="""
+device.load_merge_candidate(
+    config="""
 uci set system.@system[0].hostname='my-router'
 uci set network.lan.ipaddr='10.0.0.1'
-""")
+"""
+)
 
 print(device.compare_config())
 device.commit_config()