Adjust fake ipv6 in tests to follow specification

[frantisekz]

Makes the testsuite pass with httpx 0.24 (which otherwise fails on verification as the previous value didn't use eg. :: or hex chars)

I'd used ipv6 for local, not sure if it has any unwanted implications?

[codecov-commenter]

Codecov Report

Patch and project coverage have no change.

Comparison is base (42930fc) 100.00% compared to head (9aef400) 100.00%.

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #231 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 20 20 Lines 2755 2755 Branches 417 417 ========================================= Hits 2755 2755 ``` | [Impacted Files](https://app.codecov.io/gh/lundberg/respx/pull/231?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Jonas+Lundberg) | Coverage Δ | | |---|---|---| | [tests/test\_patterns.py](https://app.codecov.io/gh/lundberg/respx/pull/231?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Jonas+Lundberg#diff-dGVzdHMvdGVzdF9wYXR0ZXJucy5weQ==) | `100.00% <ø> (ø)` | |

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[lundberg]

Noticed this failing test as well, thanks for the PR @frantisekz 👍

[lundberg]

I opened #232 that upgrades CI requirements, could you redirect this PR to merge into the bump-ci branch so that checks passes.

[frantisekz]

I opened #232 that upgrades CI requirements, could you redirect this PR to merge into the bump-ci branch so that checks passes.

Sorry for the delay, redirected :)