Update GnosisSafeProxyFactory.sol

[Frenchkebab]

typo: 'contact' -> 'contract'

[github-actions]

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[coveralls]

Pull Request Test Coverage Report for Build 3763682344

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+1.6%) to 98.891%

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Totals
Change from base Build 3725286776:	1.6%
Covered Lines:	301
Relevant Lines:	301

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💛 - Coveralls

[mmv08]

Thanks, this will be tackled in #468