The previous fix (47a60b7) escaped the functional \$PHPIZE_DEPS
reference but added an explanatory comment that itself used several
bare/example $ characters (${PHPIZE_DEPS}, $PHPIZE_DEPS, $IDENTIFIER,
${IDENTIFIER}, and a bare $ before a comma). SimpleTemplateEngine
parses the ENTIRE file as template source, comments included, so any
of those threw either MissingPropertyException or a harder
'illegal string body character after dollar sign' parse error
depending on what followed the $.
Rewrote the comment to explain the rule in prose without using the $
glyph as an illustrative example at all, so future edits to the
comment can't reintroduce this. Verified via grep across all five
fallback Dockerfiles that the only remaining $ occurrences are the
intentional ${version} placeholders plus the one properly-escaped
\$PHPIZE_DEPS.
Mukul Sharma
f448f204e2