build: add go 1.21 (#167)

.github/ISSUE_TEMPLATE/bug-report.yml

@@ -18,6 +18,8 @@ body:
       description: What version of the library are you using or which versions do you see the issue in?
       multiple: true
       options:
+        - 0.8.6
+        - 0.8.5
         - 0.8.4
         - 0.8.3
         - 0.8.2

.github/workflows/go.yml

@@ -10,6 +10,7 @@ jobs:
           - '1.18'
           - '1.19'
           - '1.20'
+          - '1.21'
       fail-fast: false
     steps:
       - name: Set up Go ${{ matrix.go }}

.renovaterc

@@ -1,7 +1,7 @@
 {
   "$schema": "https://docs.renovatebot.com/renovate-schema.json",
   "constraints": {
-    "go": "1.20"
+    "go": "1.21"
   },
   "extends": [
     "config:base",

README.md

@@ -18,6 +18,24 @@ libraries.
 It is distributed under the same 3-Clause BSD license as the original fork, with the only amendment being the additional
 3-Clause BSD license attributing license rights to this repository.
 
+## Go Version Support Policy
+
+This library will officially support versions of go which are currently supported by the go maintainers (usually 3
+minor versions) with a brief transition time (usually 1 patch release of go, for example if go 1.21.0 is released, we
+will likely still support go 1.17 until go 1.21.1 is released). 
+
+This library in our opinion handles a critical element of security in a dependent project and we aim to avoid backwards
+compatability at the cost of security wherever possible. We also consider this especially important in a language like
+go where their backwards compatibility when upgrading the compile tools is usually flawless.
+
+This policy means that users who wish to build this with older versions of go may find there are features being used
+which are not available in that version. The current intentionally supported versions of go are as follows:
+
+- go 1.21
+- go 1.20
+- go 1.19
+- go 1.18
+
 ## Status
 
 This library is still version 0, as per Semantic Versioning 2.0 rules there may be breaking changes without warning. 

go.mod

@@ -1,6 +1,6 @@
 module github.com/go-webauthn/webauthn
 
-go 1.20
+go 1.21
 
 require (
 	github.com/fxamacker/cbor/v2 v2.4.0