fix empty img tag occupy 20px size in safari.

[suzp1984]

the html img tag occupy 20px size in safari. https://github.com/ossrs/srs/blob/427104f1dab86f5afc7d7b49b02ed27d03ef9346/trunk/research/players/rtc_player.html#L19

(ignore the img css warning: auto\9; it's another problem, I will file another PR.)

but, the empty img tag just occupy 1px size in chrome. So I guess it's a html compatible problem.

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TRANS_BY_GPT4

[suzp1984]

I guess the //ossrs.net/gif/v1/sls.gif?site=ossrs.net&path=/console/enindex is used for statistics & analysis purpose. but pls pay attention to the path, for some one may not so match with its real path.

e.g. https://github.com/ossrs/srs/blob/427104f1dab86f5afc7d7b49b02ed27d03ef9346/trunk/research/console/ng_index.html#L23 https://github.com/ossrs/srs/blob/427104f1dab86f5afc7d7b49b02ed27d03ef9346/trunk/research/players/srs_gb28181.html#L31 https://github.com/ossrs/srs/blob/427104f1dab86f5afc7d7b49b02ed27d03ef9346/trunk/research/players/whep.html#L19 https://github.com/ossrs/srs/blob/427104f1dab86f5afc7d7b49b02ed27d03ef9346/trunk/research/players/whip.html#L19