fix(Docker): point to merged branch
fix(Docker): point to merged branch

This commit fix a bug during the `docker build`:

```
Step 7/13 : RUN git clone -b add/bigquery https://github.com/vsoch/som
 ---> Running in d1df9d248617
Cloning into 'som'...
fatal: Remote branch add/bigquery not found in upstream origin
The command '/bin/sh -c git clone -b add/bigquery https://github.com/vsoch/som' returned a non-zero code: 128
```

This is due to the clone of a non existing branch (bigquery) which has been merged into master in the commit d11633161c735b4d1ef69fe3eeeb9d2474e9c2df.
Now, we can use master.

pydicom/sendit,pydicom/sendit,pydicom/sendit,pydicom/sendit