Queries are incorrectly joined back together resulting in syntax errors

### Steps to reproduce

With this query

```
SELECT AVG(Price), Manufacturer
FROM Products
GROUP BY Manufacturer;
```
It will fail as it is joined back together as

```
SELECT AVG(Price), Manufacturer FROM ProductsGROUP BY Manufacturer;
```

Whereas it works fine with
(Note the space before `GROUP`
```
SELECT AVG(Price), Manufacturer
FROM Products
GROUP BY Manufacturer;
```
It will be joined back together as

```
SELECT AVG(Price), Manufacturer FROM Products GROUP BY Manufacturer;
```
### Actual behaviour
```
SELECT AVG(Price), Manufacturer
FROM Products
GROUP BY Manufacturer;
```

is joined as

```
SELECT AVG(Price), Manufacturer FROM ProductsGROUP BY Manufacturer;
```

### Expected behaviour

The query is joined back as

```
SELECT AVG(Price), Manufacturer FROM Products GROUP BY Manufacturer;
```