update example versions, fix up links, drop old caveat

"Environment reference" got removed in favor of other pages.
The forum to report bugs has been closed for some time.
The caveat about %TEMP% was removed as a "won't fix" issue.

And the link just contributed by someone else was in French.

README.md

@@ -13,14 +13,14 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.20.x, 1.21.x]
+        go-version: [1.21.x, 1.22.x]
         os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v3
-    - uses: actions/setup-go@v4
+    - uses: actions/setup-go@v5
       with:
         go-version: ${{ matrix.go-version }}
+    - uses: actions/checkout@v4
     - run: go test ./...
 ```
 
@@ -121,7 +121,7 @@ workflow triggers, or to set up dependencies via
 
 #### How do I set up a secret environment variable?
 
-Follow [these steps](https://docs.github.com/en/actions/security-guides/encrypted-secrets)
+Follow [these steps](https://docs.github.com/en/actions/security-guides/using-secrets-in-github-actions)
 to set up the secret in the repo's settings. After adding a secret like
 `FOO_SECRET`, use it on a step as follows:
 
@@ -138,7 +138,9 @@ your own proxy. You'll need to add a
 [personal access token](https://github.com/settings/tokens) as a secret
 environment variable, as well as configure
 [GOPRIVATE](https://go.dev/ref/mod#private-modules).
-You can also directly used the token provided by [GitHub](https://docs.github.com/fr/enterprise-cloud@latest/actions/security-guides/automatic-token-authentication#using-the-github_token-in-a-workflow) in the workflow.
+You can also directly used the token
+[provided by GitHub](https://docs.github.com/en/enterprise-cloud@latest/actions/security-guides/automatic-token-authentication#using-the-github_token-in-a-workflow)
+in the workflow.
 You can define anything as username in the URL, it is not taken into account by GitHub.
 
 ```yaml
@@ -189,9 +191,7 @@ jobs:
 
 * Syntax and fields reference: https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions
 
-* Environment reference: https://docs.github.com/en/actions/using-github-hosted-runners/about-github-hosted-runners
-
-* To report bugs: https://github.com/orgs/community/discussions/categories/actions-and-packages
+* GitHub-hosted runners: https://docs.github.com/en/actions/using-github-hosted-runners/about-github-hosted-runners/about-github-hosted-runners
 
 ## Caveats
 
@@ -204,16 +204,3 @@ following `.gitattributes`:
 ```gitattributes
 * -text
 ```
-
-* https://github.com/actions/runner-images/issues/712
-
-`os.TempDir` on Windows will contain a short name, since `%TEMP%` also contains
-it. Note that case sensitivity doesn't matter, and that `os.Open` should still
-work; but some programs not treating short names might break.
-
-```cmd
-> echo %USERPROFILE%
-C:\Users\runneradmin
-> echo %TEMP%
-C:\Users\RUNNER~1\AppData\Local\Temp
-```