Use Botan 3.10.0 for tests

Clean up leak-detective whitelist for newer Botan versions but add
`botan_private_key_load` as `botan_privkey_load*` won't show up anymore
without bfd-backtraces due to inlining if we don't call it directly.

Ref: https://github.com/randombit/botan/discussions/4868

testing/scripts/recipes/011_botan.mk

@@ -2,7 +2,7 @@
 
 PKG = botan
 SRC = https://github.com/randombit/$(PKG).git
-REV = 3.7.1
+REV = 3.10.0
 
 NUM_CPUS := $(shell getconf _NPROCESSORS_ONLN)