Task/key name safe replacement

[chwagssd]

• change #some-key and :some-key to take into account a string that is not allowed to be used in ExpresssionAttributeNames
  • before, this would throw an error during the DB update updateExpression({'some-key': true})
  • even though 'some-key' is valid as an attribute for a db row in dynamodb, just not as an alias
• updated all of the paths inside of updateExpression() so that consistently makes the key name safe before using it as an alias, not just using it as-is
• actual key is untouched and still used in the write as the attribute

//before
updateExpression({'some-var': 'some value'});
/* this would actually cause an error when executing the update because of the hyphens in #some-var and :some-var
{
            
            ExpressionAttributeNames: {
              '#some-var': 'some-var'
            },
            ExpressionAttributeValues: {
              ':some-var': 'some value'
            },
            UpdateExpression:
              'SET #some-var = :some-var',
            ReturnValues: 'ALL_NEW',
          }
*/

//after
updateExpression({'some-var': 'some value'});
/*
{
            
            ExpressionAttributeNames: {
              '#some_x2d_var': 'some-var'
            },
            ExpressionAttributeValues: {
              ':some_x2d_var': 'some value'
            },
            UpdateExpression:
              'SET #some_x2d_var = :some_x2d_var',
            ReturnValues: 'ALL_NEW',
          }
*/