git: remove unused name matrix parameter from Ubuntu builds

[codecov-commenter]

Codecov Report

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

Project coverage is 1.51%. Comparing base (4e2c1d2) to head (2cde520).

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #1701 +/- ## ====================================== Coverage 1.51% 1.51% ====================================== Files 275 275 Lines 27008 27008 Branches 14474 14474 ====================================== Hits 409 409 Misses 26341 26341 Partials 258 258 ```

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