build: bump builder image to Go 1.25

go.mod requires go 1.25.0, but the Dockerfile still pinned the builder to
1.18, which cannot parse a three-part version string and failed with
"invalid go version '1.25.0': must match format 1.23".

Track the 1.25 tag rather than a patch release so the builder does not
drift out of date again.

1 files changed, 1 insertions, 1 deletions

diff --git a/Dockerfile b/Dockerfile
index fdc1919..719eab6 100755
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-ARG GO_VERSION=1.18
+ARG GO_VERSION=1.25
 
 FROM --platform=$BUILDPLATFORM golang:${GO_VERSION} AS build
 ARG TARGETOS