Another worst case quadratic complexity in HTMLParser

[serhiy-storchaka]

Linked PRs

• gh-153030: Fix quadratic complexity in incremental parsing in HTMLParser #153031
• [3.15] gh-153030: Fix quadratic complexity in incremental parsing in HTMLParser (GH-153031) #153038
• [3.14] gh-153030: Fix quadratic complexity in incremental parsing in HTMLParser (GH-153031) #153039
• [3.13] gh-153030: Fix quadratic complexity in incremental parsing in HTMLParser (GH-153031) #153040
• [3.12] gh-153030: Fix quadratic complexity in incremental parsing in HTMLParser (GH-153031) #153041
• [3.11] gh-153030: Fix quadratic complexity in incremental parsing in HTMLParser (GH-153031) #153042
• [3.10] gh-153030: Fix quadratic complexity in incremental parsing in HTMLParser (GH-153031) #153043