chore: bump toolchain to go1.25.11 and x/net to v0.53.0

Fixes 4 vulnerabilities reported by govulncheck:
- GO-2026-5039: net/textproto arbitrary input in errors (fixed go1.25.11)
- GO-2026-5037: crypto/x509 inefficient hostname parsing (fixed go1.25.11)
- GO-2026-4971: net panic on NUL byte on Windows (fixed go1.25.10)
- GO-2026-4918: infinite loop in HTTP/2 transport (fixed x/net@v0.53.0 + go1.25.10)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: ihudak

go.mod

@@ -1,8 +1,8 @@
 module github.com/dynatrace-oss/dtmgd
 
-go 1.25
+go 1.25.0
 
-toolchain go1.25.9
+toolchain go1.25.11
 
 require (
 	github.com/adrg/xdg v0.5.3
@@ -29,6 +29,6 @@ require (
 	github.com/olekukonko/errors v1.2.0 // indirect
 	github.com/olekukonko/ll v0.1.6 // indirect
 	github.com/spf13/pflag v1.0.9 // indirect
-	golang.org/x/net v0.43.0 // indirect
-	golang.org/x/sys v0.35.0 // indirect
+	golang.org/x/net v0.53.0 // indirect
+	golang.org/x/sys v0.43.0 // indirect
 )

go.sum

@@ -51,9 +51,13 @@ github.com/zalando/go-keyring v0.2.8/go.mod h1:tsMo+VpRq5NGyKfxoBVjCuMrG47yj8cma
 go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
 golang.org/x/net v0.43.0 h1:lat02VYK2j4aLzMzecihNvTlJNQUq316m2Mr9rnM6YE=
 golang.org/x/net v0.43.0/go.mod h1:vhO1fvI4dGsIjh73sWfUVjj3N7CA9WkKJNQm2svM6Jg=
+golang.org/x/net v0.53.0 h1:d+qAbo5L0orcWAr0a9JweQpjXF19LMXJE8Ey7hwOdUA=
+golang.org/x/net v0.53.0/go.mod h1:JvMuJH7rrdiCfbeHoo3fCQU24Lf5JJwT9W3sJFulfgs=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.35.0 h1:vz1N37gP5bs89s7He8XuIYXpyY0+QlsKmzipCbUtyxI=
 golang.org/x/sys v0.35.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+golang.org/x/sys v0.43.0 h1:Rlag2XtaFTxp19wS8MXlJwTvoh8ArU6ezoyFsMyCTNI=
+golang.org/x/sys v0.43.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
 golang.org/x/time v0.12.0 h1:ScB/8o8olJvc+CQPWrK3fPZNfh7qgwCrY0zJmoEQLSE=
 golang.org/x/time v0.12.0/go.mod h1:CDIdPxbZBQxdj6cxyCIdrNogrJKMJ7pr37NYpMcMDSg=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=