Simplify argument parsing (#459)

With the current state of automation scripts, this is not possible anymore to launch script with multiple auto configs.

src/rds.py

@@ -1,6 +1,7 @@
 import logging
 
-from common import dates, http, releasedata
+from common import dates, http
+from common.releasedata import ProductData, config_from_argv
 
 """Fetches Amazon RDS versions from the version management pages on AWS docs.
 
@@ -8,22 +9,22 @@ Pages parsed by this script are expected to have version tables with a version i
 in the third column (usually named 'RDS release date').
 """
 
-for config in releasedata.list_configs_from_argv():
-    with releasedata.ProductData(config.product) as product_data:
-        html = http.fetch_html(config.url)
+config = config_from_argv()
+with ProductData(config.product) as product_data:
+    html = http.fetch_html(config.url)
 
-        for table in html.find_all("table"):
-            for row in table.find_all("tr"):
-                columns = row.find_all("td")
-                if len(columns) <= 3:
-                    continue
+    for table in html.find_all("table"):
+        for row in table.find_all("tr"):
+            columns = row.find_all("td")
+            if len(columns) <= 3:
+                continue
 
-                version_text = columns[0].text.strip()
-                version_match = config.first_match(version_text)
-                if not version_match:
-                    logging.warning(f"Skipping {version_text}: does not match any version pattern")
-                    continue
+            version_text = columns[0].text.strip()
+            version_match = config.first_match(version_text)
+            if not version_match:
+                logging.warning(f"Skipping {version_text}: does not match any version pattern")
+                continue
 
-                version = config.render(version_match)
-                date = dates.parse_date(columns[2].text)
-                product_data.declare_version(version, date)
+            version = config.render(version_match)
+            date = dates.parse_date(columns[2].text)
+            product_data.declare_version(version, date)