Add request dependency to correct package.json (#4306)

- This was needed in mssql extension, not the main package.json

extensions/mssql/yarn.lock

@@ -321,7 +321,7 @@ execa@^0.8.0:
     signal-exit "^3.0.0"
     strip-eof "^1.0.0"
 
-extend@^3.0.0, extend@~3.0.2:
+extend@~3.0.2:
   version "3.0.2"
   resolved "https://registry.yarnpkg.com/extend/-/extend-3.0.2.tgz#f8b1136b4071fbd8eb140aff858b1019ec2915fa"
   integrity sha512-fjquC59cD7CyW6urNXK0FBufkZcoiGG80wTuPujX590cB5Ttln20E2UB4S/WARVqhXffZl2LNgS+gQdPIIim/g==
@@ -732,7 +732,7 @@ request-promise@^4.2.2:
     stealthy-require "^1.1.0"
     tough-cookie ">=2.3.3"
 
-request@^2.74.0:
+request@^2.88.0:
   version "2.88.0"
   resolved "https://registry.yarnpkg.com/request/-/request-2.88.0.tgz#9c2fca4f7d35b592efe57c7f0a55e81052124fef"
   integrity sha512-NAqBSrijGLZdM0WZNsInLJpkJokL72XYjUpnB0iwsRgxh7dB6COrHnTBNwN0E+lHDAJzu7kLAkDeY08z2/A0hg==
@@ -984,15 +984,6 @@ vscode-nls@^4.0.0:
   resolved "https://registry.yarnpkg.com/vscode-nls/-/vscode-nls-4.0.0.tgz#4001c8a6caba5cedb23a9c5ce1090395c0e44002"
   integrity sha512-qCfdzcH+0LgQnBpZA53bA32kzp9rpq/f66Som577ObeuDlFIrtbEJ+A/+CCxjIh4G8dpJYNCKIsxpRAHIfsbNw==
 
-webhdfs@^1.1.1:
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/webhdfs/-/webhdfs-1.2.0.tgz#c41b08ae33944a0220863bfd4b6719b9aaec1d37"
-  integrity sha512-h8D/NT7ruDMuGCdJNEJHJh8vDTEtZ5hBL+eRzXTq/INTd92LKOhsTCwlQI+8kTt79qPZq5O8ev7j/Y19VeYCHQ==
-  dependencies:
-    buffer-stream-reader "^0.1.1"
-    extend "^3.0.0"
-    request "^2.74.0"
-
 which@^1.2.9:
   version "1.3.1"
   resolved "https://registry.yarnpkg.com/which/-/which-1.3.1.tgz#a45043d54f5805316da8d62f9f50918d3da70b0a"