fix mssql startup (#985)

- Sleep 45s is invalid
- /opt/mssql/bin/sqlservr is the correct path for mssql binary

mssql/create_table.sh

 #wait for the SQL Server to come up
-sleep 45s
+sleep 45
 
 #run the setup script to create the DB and the schema in the DB
 /opt/mssql-tools/bin/sqlcmd -S localhost -U sa -P $SA_PASSWORD -d master -i setup.sql
\ No newline at end of file

mssql/entrypoint.sh

 #start SQL Server, start the script to create the DB and import the data, start the app
-/opt/mssql/bin/sqlservr.sh & /usr/src/app/create_table.sh & tail -f /dev/null
\ No newline at end of file
+/opt/mssql/bin/sqlservr & /usr/src/app/create_table.sh & tail -f /dev/null