update yixia_download url match rule, fix #1346 
diff --git a/src/you_get/extractors/yixia.py b/src/you_get/extractors/yixia.py
index ca5c4bd6ab..7d5ba29089 100644
--- a/src/you_get/extractors/yixia.py
+++ b/src/you_get/extractors/yixia.py
@@ -51,11 +51,11 @@ def yixia_download(url, output_dir = '.', merge = True, info_only = False, **kwa
         yixia_download_by_scid = yixia_miaopai_download_by_scid
         site_info = "Yixia Miaopai"
         
-        if re.match(r'http://www.miaopai.com/show/channel/\w+', url):  #PC
+        if re.match(r'http://www.miaopai.com/show/channel/.+', url):  #PC
             scid = match1(url, r'http://www.miaopai.com/show/channel/(.+)\.htm')
-        elif re.match(r'http://www.miaopai.com/show/\w+', url):  #PC
+        elif re.match(r'http://www.miaopai.com/show/.+', url):  #PC
             scid = match1(url, r'http://www.miaopai.com/show/(.+)\.htm')
-        elif re.match(r'http://m.miaopai.com/show/channel/\w+', url):  #Mobile
+        elif re.match(r'http://m.miaopai.com/show/channel/.+', url):  #Mobile
             scid = match1(url, r'http://m.miaopai.com/show/channel/(.+)\.htm')
     
     elif 'xiaokaxiu.com' in hostname:  #Xiaokaxiu

Miaopai has two styles of URL
1. http://www.miaopai.com/show/-FIqw~8q9R1qq~gSm0tUGA__.htm
2. http://www.miaopai.com/show/KDzmatlzeXnYSve4Z1Bdjg__.htm

and `\w` can't match style 1, so i changed `\w+` to `.+`, this could fix problem in #1346 

ping @cnbeining @soimort

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