Docs: Update parser reference to espree instead of esprima (#6404)

docs/developer-guide/architecture.md

@@ -48,7 +48,7 @@ This object may not:
 
 ## The `eslint` object
 
-The main method of the `eslint` object is `verify()` and accepts two arguments: the source text to verify and a configuration object (the baked configuration of the given configuration file plus command line options). The method first parses the given text with Esprima and retrieves the AST. The AST is produced with both line/column and range locations which are useful for reporting location of issues and retrieving the source text related to an AST node, respectively.
+The main method of the `eslint` object is `verify()` and accepts two arguments: the source text to verify and a configuration object (the baked configuration of the given configuration file plus command line options). The method first parses the given text with `espree` (or whatever the configured parser is) and retrieves the AST. The AST is produced with both line/column and range locations which are useful for reporting location of issues and retrieving the source text related to an AST node, respectively.
 
 Once the AST is available, `estraverse` is used to traverse the AST from top to bottom. At each node, the `eslint` object emits an event that has the same name as the node type (i.e., "Identifier", "WithStatement", etc.). On the way back up the subtree, an event is emitted with the AST type name and suffixed with ":after", such as "Identifier:after" - this allows rules to take action both on the way down and on the way up in the traversal. Each event is emitted with the appropriate AST node available.