RFR: Update README.md

[Jonathan Gibbons]

Joe,

I don't know if I count as a Reviewer, but the change looks good to me.

-- Jon


On 07/31/2019 10:25 AM, Joe Darcy wrote:
> PS No additional typos were found in the README.
>
> -Joe
>
> On 7/30/2019 10:48 PM, Joe Darcy via github.com wrote:
>> Fix typo in description of hgbridge.
>>
>> ----------------
>>
>> Commits:
>>   - ebd737b8:    Update README.md
>>             Fix typo in description of hgbridge.
>>
>> Pull request:
>> http://git.openjdk.java.net/skara/pull/33
>>
>> Webrev:
>> https://openjdk.github.io/cr/skara/33/webrev.00
>>
>> Patch:
>> http://git.openjdk.java.net/skara/pull/33.diff
>>
>> Fetch command:
>> git fetch https://github.com/openjdk/skara.git pull/33/head:pull/33