fix: correctly rectify Urls with dots in DeltaTableBuilder

[rtyler]

While doing some unrelated work I did some dry-by test coverage addition and discovered this issue with some of our DAT tests.

The only way I believe we can be certain our path segments don't have .. in them is to re-parse the Url 😢

[codecov]

Codecov Report

❌ Patch coverage is 84.12698% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.98%. Comparing base (864fbc0) to head (a76346b).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/core/src/table/builder.rs	37.50%	6 Missing and 4 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3929      +/-   ##
==========================================
+ Coverage   73.94%   73.98%   +0.03%     
==========================================
  Files         153      153              
  Lines       39477    39489      +12     
  Branches    39477    39489      +12     
==========================================
+ Hits        29193    29214      +21     
+ Misses       8960     8953       -7     
+ Partials     1324     1322       -2     

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[hntd187]

One question, but otherwise GTG

[hntd187]

Would this clone the string on every interspersion? Pedantic here, but maybe a const SEP: &str = "/"; would make more sense?