Work around Readthedocs command parsing bug

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index a98bec7..2b38c07 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -16,6 +16,7 @@
     - breathe-apidoc -o docs/api apidoc/xml
     post_build:
     - |
+      # Work around Readthedocs bug: Command parsing fails if the 'if' statement is on the first line
       if [ "$READTHEDOCS_VERSION" = "development" ]; then
         "$READTHEDOCS_VIRTUALENV_PATH/bin/rtd" projects "Mbed TLS API" redirects sync --wet-run -f docs/redirects.yaml
       fi