[Accessibility] Decorative images in card form missing alt="" or role="presentation" (WCAG 1.1.1)

[mark-hingston]

Several decorative images in the card payment form are missing proper accessibility attributes (alt="" or role="presentation"), causing WCAG 1.1.1 failures.

Affected elements:

• img.adyen-checkout__icon (validation icons on Name on card, Security code, Expiry date fields)
• img.adyen-checkout__field__exp-date_hint (expiry date hint icon)
• img.adyen-checkout__image.adyen-checkout__image--loaded (card brand images)

To reproduce:

1. Load the card payment Drop-in component
2. Run an accessibility scan (e.g., BrowserStack Accessibility, axe)
3. Observe violations for WCAG 1.1.1 (Non-text content) and 4.1.2 (Name, Role, Value)

Expected behaviour:
Decorative images should have alt="" or role="presentation" so assistive technologies ignore them.

SDK version: 6.22.0 (also confirmed on 6.26.0 via docs examples)