ci: fix using fmt master with OIIO main build (#2095)

A recent change in OIIO main is to check that any auto-built
dependencies have a SHA-1 hash that matches what we think it should be
for that version. That works fine for a fixed version, but if we are
asking for OIIO to build from dependency master/main, as we do from
its "bleeding edge" CI variant, we need to tell it that it's ok to not
match the expected hash by setting
OpenImageIO_DEPENDENCY_BUILD_ALLOW_UNVERIFIED_TAGS=ON.  So we need to
do this in the OSL bleeding edge variant, too.

Signed-off-by: Larry Gritz <lg@larrygritz.com>

Author: lgritz

.github/workflows/ci.yml

@@ -449,6 +449,7 @@ jobs:
                             PTEX_VERSION=v2.4.3
                             PUGIXML_VERSION=v1.15
                             FREETYPE_VERSION=VER-2-14-3
+                            OpenImageIO_DEPENDENCY_BUILD_ALLOW_UNVERIFIED_TAGS=ON
           - desc: clang14/C++17 llvm14 py3.10 avx2 batch-b16avx512
             nametag: linux-clang14
             runner: ubuntu-22.04