test: move "make build" for webpki into generate.sh (#7885)

webpki.go was discarding stdout when "make build" failed. We can make it
print stdout in that context, but it's more straightforward to run "make
build" from the shell script that calls webpki.go, where its stdout will
naturally be emitted.

Inspired by a recent CI run where there was a straightforward build
failure in some of Boulder's code, but it was masked by an error running
webpki.go in the `bsetup` container.

test/certs/generate.sh

@@ -63,6 +63,7 @@ webpki() (
   # This function executes in a subshell, so this cd does not affect the parent
   # script.
   cd ../..
+  make build
   mkdir ./test/certs/webpki
   go run ./test/certs/webpki.go
 )

test/certs/webpki.go

@@ -81,10 +81,6 @@ func main() {
 	_ = blog.Set(blog.StdoutLogger(6))
 	defer cmd.AuditPanic()
 
-	// Compile the ceremony binary for easy re-use.
-	_, err := exec.Command("make", "build").CombinedOutput()
-	cmd.FailOnError(err, "compiling ceremony tool")
-
 	// Create SoftHSM slots for the root signing keys
 	rsaRootKeySlot, err := createSlot("Root RSA")
 	cmd.FailOnError(err, "failed creating softhsm2 slot for RSA root key")