Object basics: Clearer wording/example with mutations & references

[wolfdaemon]

This changes the "Reassigning object data type variables" with revised language and an extended example to explain the concept much more initially clear.

Because

This changes the "Reassigning object data type variables" with revised language and an extended example to explain the concept much more initially clear.

This PR

• Changes the admonition titled "Reassigning object data type variables" to "Modifying the properties of an object vs. reassigning the object variables"
• Changes the verbiage/example of the section to make things more clear, specifically:
  • Making a clear difference as to what a "mutation" vs changing the value of a primitive does
    • How the above affects variables that reference vs primitives that have a value on its own
    • Making a clear separating the between the variable name that references the object itself, vs the name/label/reference attached to it.

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