ci(package-manager): update ubuntu os to latest (fastify#4591)

* ci(package-manager): update ubuntu os to latest

* docs(reference/lts): fix table formatting

Author: Fdawgs

.github/workflows/package-manager-ci.yml

@@ -16,7 +16,7 @@ jobs:
       matrix:
         # Maintenance and active LTS
         node-version: [14, 16]
-        os: [ubuntu-18.04]
+        os: [ubuntu-latest]
 
     steps:
       - uses: actions/checkout@v3
@@ -44,7 +44,7 @@ jobs:
       matrix:
         # Maintenance and active LTS
         node-version: [14, 16]
-        os: [ubuntu-18.04]
+        os: [ubuntu-latest]
 
     steps:
       - uses: actions/checkout@v3

docs/Reference/LTS.md

@@ -62,7 +62,7 @@ YAML workflow labels below:
 | OS      | YAML Workflow Label    | Package Manager           | Node.js      |
 |---------|------------------------|---------------------------|--------------|
 | Linux   | `ubuntu-latest`        | npm                       | 14,16,18     |
-| Linux   | `ubuntu-18.04`         | yarn,pnpm                 | 14,16,18     |
+| Linux   | `ubuntu-latest`        | yarn,pnpm                 | 14,16,18     |
 | Windows | `windows-latest`       | npm                       | 14,16,18     |
 | MacOS   | `macos-latest`         | npm                       | 14,16,18     |