app-text/typst: update version env vars to new format

typst’s build script failed to parse the version string as it was
defined in the previous commit.

Signed-off-by: odrling <florianbadie@odrling.xyz>

app-text/typst/typst-0.15.0.ebuild

@@ -66,7 +66,8 @@ src_prepare() {
 src_compile() {
 	if [[ ${PV} != 9999 ]]; then
 		local GIT_HASH=$(gunzip < "${DISTDIR}/${P}.tar.gz" | git get-tar-commit-id)
-		export TYPST_VERSION="${PV} (${GIT_HASH::8})"
+		export TYPST_COMMIT_SHA="${GIT_HASH}"
+		export TYPST_VERSION="${PV}"
 	fi
 	export GEN_ARTIFACTS="artifacts/"