fix base type once Signal is float in Fibex

[Dalilaroussi]

@ebroecker , based on the specification , once SIG_VALTYPE is 1 or 2 it's float , this need to be fixed in fibex

[github-actions]

Pull Request Test Coverage Report for Build 11236996599

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 1 of 24 (4.17%) changed or added relevant lines in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.03%) to 53.344%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/canmatrix/formats/fibex.py	1	24	4.17%

Files with Coverage Reduction	New Missed Lines	%
src/canmatrix/formats/fibex.py	2	6.57%

Totals
Change from base Build 10935562972:	-0.03%
Covered Lines:	4459
Relevant Lines:	8359

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