feat: add Linux distributions to the os context (#1227)

* feat: add Linux distributions to the os context

* Link to official docs and a list of distribution identifiers

Also mention the /etc/os-release keys and how they map to the ones in the distribution object.

Author: supervacuus

src/docs/sdk/event-payloads/contexts.mdx

@@ -273,6 +273,14 @@ output of the `uname` syscall.
 system. For some well-known runtimes, Sentry will attempt to parse `name` and
 `version` from this string, if they are not explicitly given.
 
+`distribution`
+
+: _Optional_. An object that provides meta-data for Linux distributions. The values correspond to entries from the [`/etc/os-release`](https://www.freedesktop.org/software/systemd/man/latest/os-release.html#Options) configuration. Contains the following keys:
+
+- `name`: A stable name for each distribution. This maps to `ID` in `/etc/os-release` (examples: `ubuntu`, `rhel`, `alpine`; a full list of tested identifiers is available in the [Native SDK repository](https://github.com/getsentry/sentry-native/blob/master/tests/fixtures/os_releases/distribution_names.txt).
+- `version`: _Optional_. Typically identifies at least the major release version number. This maps to `VERSION_ID` in `/etc/os-release`. Distributions with rolling releases only, will not provide a version.
+- `pretty_name`: _Optional_. Typically provides the full name, full version, and release alias. This maps to `PRETTY_NAME` in `/etc/os-release` (examples: `Ubuntu 22.04.4 LTS`, `Raspian GNU/Linux 10 (buster)`).
+
 ### Example OS Context
 
 The OS Context for the 3 major OSs should look like this:
@@ -295,8 +303,12 @@ The OS Context for the 3 major OSs should look like this:
   "linux": {
     "type": "os",
     "name": "Linux",
-    "version": "5.10.6",
-    "build": "arch1-1"
+    "version": "6.1.82(99.168.amzn2023.x86_64)",
+    "distribution": {
+      "name": "amzn",
+      "version": "2023",
+      "pretty_name": "Amazon Linux 2023.4.20240401"
+    }
   }
 }
 ```