tools: Modify update-locked-requirements to take optional arguments.

This commit modifies the `update-locked-requirements` tool to take
output file path as optional arguments.

tools/update-locked-requirements

@@ -40,5 +40,30 @@ EOF
     ) | sponge "$output"
 }
 
-compile_requirements requirements/prod.txt requirements/prod_lock.txt
+OUTPUT_PROD_FILE='requirements/prod_lock.txt'
-compile_requirements requirements/dev.txt requirements/dev_lock.txt
+OUTPUT_DEV_FILE='requirements/dev_lock.txt'
+
+# Parse arguments.
+if [ $# -gt 0 ]; then
+    while [ "$1" != "" ]; do
+        case $1 in
+            --prod)
+                shift
+                OUTPUT_PROD_FILE="$1"
+                ;;
+            --dev)
+                shift
+                OUTPUT_DEV_FILE="$1"
+                ;;
+            *)
+                echo "Invalid arguments passed."
+                echo "Usage: $0 [--prod <prod-lock-file-path> --dev <dev-lock-file-path>]"
+                exit
+                ;;
+        esac
+        shift
+    done
+fi
+
+compile_requirements requirements/prod.txt $OUTPUT_PROD_FILE
+compile_requirements requirements/dev.txt $OUTPUT_DEV_FILE