Fix aws_host_utils_is_ipv6 function

[waahm7]

Description of changes:

• The host will always be stripped of [] and will never be enclosed in it.

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 83.12%. Comparing base (24e2396) to head (8a280d6).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1114 +/- ## ========================================== - Coverage 83.14% 83.12% -0.03% ========================================== Files 56 56 Lines 5760 5753 -7 ========================================== - Hits 4789 4782 -7 Misses 971 971 ```

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