updated npm supported versions (#17739)

Author: hubwriter

data/reusables/dependabot/supported-package-managers.md

@@ -8,7 +8,7 @@ Package manager | YAML value | Supported versions | Private repositories | Vendo
 --- | --- | --- |:---:|:---:
 Bundler | `bundler` | v1 | | **✓** |
 Cargo | `cargo` | v1 | **✓** | |
-Composer | `composer` | v1,v2  | **✓** | |
+Composer | `composer` | v1, v2  | **✓** | |
 Docker | `docker` | v1 | **✓** | |
 Elixir | `mix` | v1 | **✓** | |
 Elm | `elm` | v0.18, v0.19 | **✓** | |
@@ -17,7 +17,7 @@ GitHub Actions | `github-actions` |  N/A (no version) | **✓** | |
 Go modules | `gomod` | v1 | **✓** | **✓** |
 Gradle | `gradle` | see (A) below | **✓** | |
 Maven | `maven` | see (B) below | **✓** | |
-npm | `npm` | v6 | **✓** | |
+npm | `npm` | v6, v7 | **✓** | |
 NuGet | `nuget` | <= 4.8.</br>see (C) below | **✓** | |
 pip | `pip` | v20 | | |
 pipenv | `pip` | <= 2018.11.26 | | |