readthedocs: fix the build.os

Set build.os to ubuntu-22.04 to fix the config issue:

```
Invalid configuration option "build.os": expected one of (ubuntu-20.04,
ubuntu-22.04), got latest
```

Issue-ID: INF-438

Signed-off-by: Jackie Huang <jackie.huang@windriver.com>
Change-Id: I1f1bf70a6cd5f6b9ef1710d4f41519ce6ccca491

diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 243587e..19b2821 100644 (file)
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -9,7 +9,7 @@ formats:
   - htmlzip
 
 build:
-  os: latest
+  os: ubuntu-22.04
   tools:
     python: "3.7"