[Eric] error using git

[Ian Proudler]

I am getting the following error when trying to use git (v2.17.1).

(Apologies if this not the correct place to report the issue. I briefly 
saw an email address when the error first occurred but can't remember it)

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2019-05-05, 17:58:58
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<class 'AttributeError'>:
'NoneType' object has no attribute 'vcsDiff'
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   File 
"/home/ian/eric_venv/lib/python3.6/site-packages/eric6/VCS/ProjectHelper.py", 
line 544, in _vcsDiff
     self.vcs.vcsDiff(self.project.ppath)

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Version Numbers:
   Python 3.6.7, 64-Bit
   Qt 5.12.2
   PyQt 5.12.1
   sip 4.19.15
   QScintilla 2.11.1
   WebEngine 69.0.3497.128
   eric6 19.5 (rev. 68256afbba26)

Platform: linux
3.6.7 (default, Oct 22 2018, 11:32:17)
[GCC 8.2.0]

Desktop: XFCE
--------------------------------------------------------------------------------
Plugins Version Numbers:
   PluginAbout 19.5
   PluginCodeStyleChecker 19.5
   PluginEricapi 19.5
   PluginEricdoc 19.5
   PluginSyntaxChecker 19.5
   PluginTabnanny 19.5
   PluginTranslator 19.5
   PluginVcsGit 19.5
   PluginVcsMercurial 19.5
   PluginVcsPySvn 19.5
   PluginVcsSubversion 19.5
   PluginVmListspace 19.5
   PluginVmTabview 19.5
   PluginWizardDotDesktop 19.5
   PluginWizardE5MessageBox 19.5
   PluginWizardEricPlugin 19.5
   PluginWizardPyRegExp 19.5
   PluginWizardQColorDialog 19.5
   PluginWizardQFileDialog 19.5
   PluginWizardQFontDialog 19.5
   PluginWizardQInputDialog 19.5
   PluginWizardQMessageBox 19.5
   PluginWizardQRegExp 19.5
   PluginWizardQRegularExpression 19.5
   PluginWizardSetup 19.5
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Distribution Info:
   /etc/lsb-release
   DISTRIB_ID=Ubuntu
   DISTRIB_RELEASE=18.04
   DISTRIB_CODENAME=bionic
   DISTRIB_DESCRIPTION="Ubuntu 18.04.2 LTS"

   /etc/os-release
   NAME="Ubuntu"
   VERSION="18.04.2 LTS (Bionic Beaver)"
   ID=ubuntu
   ID_LIKE=debian
   PRETTY_NAME="Ubuntu 18.04.2 LTS"
   VERSION_ID="18.04"
   HOME_URL="https://www.ubuntu.com/"
   SUPPORT_URL="https://help.ubuntu.com/"
   BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
   VERSION_CODENAME=bionic
   UBUNTU_CODENAME=bionic