fix: only require http api client if it has not been specified

If we configure which http api module to use, don't try to require
`ipfs-http-client`, because that then means the containing project
needs to specify a dependency on `ipfs-http-client` when the
containing project might actually be `ipfs-http-client`...

Author: achingbrain

src/factory.js

@@ -21,10 +21,6 @@ const defaults = {
   type: 'go',
   env: {},
   args: [],
-  ipfsHttpModule: {
-    path: require.resolve('ipfs-http-client'),
-    ref: require('ipfs-http-client')
-  },
   ipfsOptions: {},
   forceKill: true,
   forceKillTimeout: 5000
@@ -109,6 +105,15 @@ class Factory {
       options
     )
 
+    // only include the http api client if it has not been specified as an option
+    // for example if we are testing the http api client itself
+    if (!opts.ipfsHttpModule) {
+      opts.ipfsHttpModule = {
+        path: require.resolve('ipfs-http-client'),
+        ref: require('ipfs-http-client')
+      }
+    }
+
     // conditionally include ipfs based on which type of daemon we will spawn when none has been specifed
     if ((opts.type === 'js' || opts.type === 'proc') && !opts.ipfsModule) {
       opts.ipfsModule = {