ci: update memcheck suppression stack signature (#2913)

**What problem is this PR intended to solve?**

See recent failures in upstream.yml, e.g.
https://github.com/sparklemotion/nokogiri/actions/runs/5354163940/jobs/9710862134

Something changed recently, not sure if it's the compiler in CI, or the
library, or a combination.

suppressions/ruby.supp

@@ -98,7 +98,7 @@
  fun:evaluate
 }
 {
- TODO
+ https://github.com/sparklemotion/nokogiri/actions/runs/5354163940/jobs/9710862134
  # 240 (120 direct, 120 indirect) bytes in 1 blocks are definitely lost in loss record 28,980 of 37,883
  # *xmlNewNodeEatName (tree.c:2299)
  # *xmlNewDocNodeEatName (tree.c:2374)
@@ -117,7 +117,7 @@
  fun:xmlNewNodeEatName
  fun:xmlNewDocNodeEatName
  fun:xmlSAX2StartElementNs
- fun:xmlParseStartTag2
+ fun:xmlParseStartTag*
  fun:xmlParseElementStart
  fun:xmlParseContentInternal
  fun:xmlParseElement