speedtest-cli: add --csv and --json examples (#4465)

pages/common/speedtest-cli.md

@@ -7,6 +7,10 @@
 
 `speedtest-cli`
 
+- Run without performing download tests:
+
+`speedtest-cli --no-download`
+
 - Run a speed test and generate a shareable result picture:
 
 `speedtest-cli --share`
@@ -18,3 +22,11 @@
 - Run a speed test to the given speedtest.net server id:
 
 `speedtest-cli --server {{server_id}}`
+
+- Display results in CSV format, suppressing the progress information:
+
+`speedtest-cli --csv --csv-delimiter {{delimiter_char}}`
+
+- Display results in JSON format, suppressing the progress information:
+
+`speedtest-cli --json`