chore(python-library): use sphinx 1.5.5 for the docfx job

Originally tested at:
googleapis/python-texttospeech#89

This change will fix the missing docstring in the yaml files.

Source-Author: Takashi Matsuo <[email protected]>
Source-Date: Thu Sep 10 04:12:14 2020 +0000
Source-Repo: googleapis/synthtool
Source-Sha: ffcee7952b74f647cbb3ef021d95422f10816fca
Source-Link: googleapis/synthtool@ffcee79

Author: yoshi-automation

docs/conf.py

@@ -29,7 +29,7 @@
 # -- General configuration ------------------------------------------------
 
 # If your documentation needs a minimal Sphinx version, state it here.
-needs_sphinx = "1.6.3"
+needs_sphinx = "1.5.5"
 
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom

synth.metadata

@@ -11,15 +11,15 @@
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "48ce8878cd4c54cf247de826ac53c1414b0345bd",
-        "internalRef": "330504082"
+        "sha": "3293ef20c714bb005f6a9c987e2ae8a1ad745272",
+        "internalRef": "330824843"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "d302f93d7f47e2852e585ac35ab2d15585717ec0"
+        "sha": "ffcee7952b74f647cbb3ef021d95422f10816fca"
       }
     }
   ],