x/net/http2: server_test.go has a Fatalf call with %q on wrong type int64

[gopherbot]

#!watchflakes
default <- pkg == "golang.org/x/net/http2" && test == "" && `Fatalf format %q has arg r.ContentLength of wrong type int64`

Issue created automatically to collect these failures.

Example (log):

FAIL	golang.org/x/net/http2 [build failed]
# golang.org/x/net/http2
# [golang.org/x/net/http2]
http2/server_test.go:1980:21: (testing.TB).Fatalf format %q has arg r.ContentLength of wrong type int64

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "golang.org/x/net/http2" && test == ""

2025-11-22 00:46 x_net-gotip-linux-amd64-tiplang net@346cc615 go@58a48a3e x/net/http2 (log)

FAIL	golang.org/x/net/http2 [build failed]
# golang.org/x/net/http2
# [golang.org/x/net/http2]
http2/server_test.go:1980:21: (testing.TB).Fatalf format %q has arg r.ContentLength of wrong type int64

— watchflakes

[gopherbot]

Change https://go.dev/cl/725220 mentions this issue: http2, webdav, websocket: fix %q verb uses with wrong type