Simplify re-raise for non-legacy

[Glutexo]

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Complete Description of Additions/Changes:

To avoid confusion for developers, removed the unnecessary conditional for exception re-raise.

• It is unnecessary to set last_ex on non-legacy, because there is no fallback to other URLs. Only one URL is tried and if it fails, there is only a single exception.
• The if last_ex condition can never be false, because if an exception is not raised, the function hits a return clause earlier. It only gets to the conditional if an exception has been caught.

A simple raise is enough. Without an argument, the last caught exception is re-raised by default. It’s thus equivalent to raise exc.

Card IDs:

• CCT-867