README: remove Azure Pipelines badge.
README: remove Azure Pipelines badge.

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MikeMcQuaid/brew,vitorgalvao/brew,EricFromCanada/brew,claui/brew,EricFromCanada/brew,EricFromCanada/brew,MikeMcQuaid/brew,Homebrew/brew,Homebrew/brew,claui/brew,JCount/brew,EricFromCanada/brew,nandub/brew,claui/brew,mahori/brew,konqui/brew,mahori/brew,vitorgalvao/brew,nandub/brew,konqui/brew,vitorgalvao/brew,JCount/brew,mahori/brew,reitermarkus/brew,reitermarkus/brew,sjackman/homebrew,mahori/brew,sjackman/homebrew,claui/brew,sjackman/homebrew,nandub/brew,Homebrew/brew,reitermarkus/brew,sjackman/homebrew,konqui/brew,MikeMcQuaid/brew,MikeMcQuaid/brew,konqui/brew,JCount/brew,vitorgalvao/brew,nandub/brew,Homebrew/brew,reitermarkus/brew,JCount/brew