Avoids treating HTML entity encoded braces (e.g., {{) as interpolation delimiters.

fixes #62174

What is the current behavior?

@Component({
 template: `
   {{ demo }}
 `,
})
class App { }

throw

NG5002: Parser Error: Blank expressions are not allowed in interpolated strings at column 1 in [ {{ }} ] 

Does this PR introduce a breaking change?

• Yes
• No

Other information

Another option would be to improve the message so it points to a valid workaround when we detect entity encoding, since I’ve also run into this issue when asking AI agents (e.g., GitHub Copilot) to write documentation or examples.