[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```

[Java] Fix literal backslash in strings (#4038)

This commit removes `invalid.illegal` scope from unsupported escape sequences.

Actually `\` is interpreted literal if it doesn't start a supported escape
sequence.

The following is a valid string without illegals:

```
new Source("src\main\java\com\example\application\views\HomeView.java")
```