fix: Make NodeBalancer.tags mutable - #371

📝 Description

This change makes the NodeBalancer.tags attribute mutable to match the PUT /nodebalancers/{id} endpoint documentation.

Additionally, this change alters the create-version Makefile target to address minor differences between how the echo command handles escape characters on different systems.

✔️ How to Test

The following test steps assume you have pulled down this PR locally.

Unit Testing

make testunit

Manual Testing

1. In a Python SDK sandbox environment (e.g. dx-devenv), run the following:

import os

from linode_api4 import LinodeClient

client = LinodeClient(token=os.getenv("LINODE_TOKEN"))

nb = client.nodebalancers.create(
    "us-mia",
    label="test-nb",
    tags=["cool"]
)

print("Original tags:", nb.tags)

nb.tags = ["foo", "bar"]
nb.label = "test-nb-updated"
nb.save()

nb.invalidate()

print("Updated & refreshed tags:", nb.tags)

2. Ensure the output matches the following:

Original tags: ['cool']
Updated & refreshed tags: ['bar', 'foo']

3. Navigate to the newly created NodeBalancer in Cloud Manager and ensure it has the tags bar and foo.