MM-31511: Fix incorrect replace repo (#16603)

The package paths were changed. Therefore, go mod tidy
on master failed with:

```
go: finding module for package github.com/hmhealey/go-opengraph/opengraph
go: found github.com/hmhealey/go-opengraph/opengraph in github.com/hmhealey/go-opengraph v0.0.0-20201209151214-f2d823730dba
go: github.com/hmhealey/go-opengraph@v0.0.0-20201209151214-f2d823730dba used for two different module paths (github.com/dyatlov/go-opengraph and github.com/hmhealey/go-opengraph)
```

https://mattermost.atlassian.net/browse/MM-31511

```release-note
NONE
```

vendor/modules.txt

@@ -144,6 +144,7 @@ github.com/blevesearch/zap/v15
 # github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869
 ## explicit
 # github.com/cespare/xxhash/v2 v2.1.1
+## explicit
 github.com/cespare/xxhash/v2
 # github.com/corpix/uarand v0.1.1
 ## explicit
@@ -161,6 +162,9 @@ github.com/couchbase/vellum/utf8
 ## explicit
 # github.com/davecgh/go-spew v1.1.1
 github.com/davecgh/go-spew/spew
+# github.com/dgrijalva/jwt-go v3.2.0+incompatible
+## explicit
+github.com/dgrijalva/jwt-go
 # github.com/dgryski/dgoogauth v0.0.0-20190221195224-5a805980a5f3
 ## explicit
 github.com/dgryski/dgoogauth
@@ -176,7 +180,7 @@ github.com/dsnet/compress/bzip2/internal/sais
 github.com/dsnet/compress/internal
 github.com/dsnet/compress/internal/errors
 github.com/dsnet/compress/internal/prefix
-# github.com/dyatlov/go-opengraph v0.0.0-20180429202543-816b6608b3c8 => github.com/hmhealey/go-opengraph v0.0.0-20201209151214-f2d823730dba
+# github.com/dyatlov/go-opengraph v0.0.0-20180429202543-816b6608b3c8 => github.com/agnivade/go-opengraph v0.0.0-20201221052033-34e69ee2a627
 ## explicit
 github.com/dyatlov/go-opengraph/opengraph
 # github.com/facebookgo/ensure v0.0.0-20200202191622-63f1cf65ac4c
@@ -919,4 +923,4 @@ willnorris.com/go/gifresize
 ## explicit
 willnorris.com/go/imageproxy
 willnorris.com/go/imageproxy/third_party/http
-# github.com/dyatlov/go-opengraph => github.com/hmhealey/go-opengraph v0.0.0-20201209151214-f2d823730dba
+# github.com/dyatlov/go-opengraph => github.com/agnivade/go-opengraph v0.0.0-20201221052033-34e69ee2a627