[3.12] gh-111380: Show SyntaxWarnings only once when parsing if invalid syntax is encouintered (GH-111381) (#111382)

gh-111380: Show SyntaxWarnings only once when parsing if invalid syntax is encouintered (GH-111381)
(cherry picked from commit 3d2f1f0b830d86f16f42c42b54d3ea4453dac318)

Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>