Add Salesforce Logo for Project Templates
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### Problem to solve
We recently updated a number of our project templates to use the proper icons. We should do the same for SalesforceDX.
### Proposal
Add the Salesforce image so that it appears properly in the project template list.
https://gitlab.com/projects/new#create_from_template
The logo today is the generic Tanuki:

### Further details
We should investigate if we need legal approval from Salesforce to use their icon.
issue