[#3919] Fix update-python-dependencies not writing to file

diff --git a/doc/sphinx/update-python-dependencies.sh.in b/doc/sphinx/update-python-dependencies.sh.in
index f6955a5600ae6b464bd7d2f9971497ecfca1d493..f496fad86d3a1e6db9db5158911bbf23c804afd8 100755 (executable)
--- a/doc/sphinx/update-python-dependencies.sh.in
+++ b/doc/sphinx/update-python-dependencies.sh.in
@@ -7,4 +7,5 @@ if test '@HAVE_PIP_COMPILE@' = 'no'; then
 fi
 
 cd '@srcdir@'
-@PIP_COMPILE@ --no-strip-extras --rebuild --upgrade ./src/requirements.in
+@PIP_COMPILE@ --no-strip-extras --output-file=./src/requirements.txt \
+    --rebuild --upgrade ./src/requirements.in