go/build: remove nonexistent package from TestDependencies

crypto/internal/boring/fips140tls is not a package in the Go standard
library, so it should not be listed in TestDependencies.

Change-Id: I6476da397b0204fcbd0a11b27a29112fca4b6023
Reviewed-on: https://go-review.googlesource.com/c/go/+/636415
Reviewed-by: Filippo Valsorda <[email protected]>
Auto-Submit: Quim Muntal <[email protected]>
Reviewed-by: David Chase <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>

Author: qmuntal

src/go/build/deps_test.go

@@ -498,7 +498,7 @@ var depsRules = `
 	FIPS, internal/godebug, hash < crypto/fips140, crypto/internal/fips140only;
 
 	NONE < crypto/internal/boring/sig, crypto/internal/boring/syso;
-	sync/atomic < crypto/internal/boring/bcache, crypto/internal/boring/fips140tls;
+	sync/atomic < crypto/internal/boring/bcache;
 	crypto/internal/boring/sig, crypto/tls/internal/fips140tls < crypto/tls/fipsonly;
 
 	# CRYPTO is core crypto algorithms - no cgo, fmt, net.