[ocamlformat] Move .ocamlformat config file to the project root

Summary:
Several tools that use ocamlformat look for the "project root" in
order to find the config for a given file to format. The project root
is inferred by looking in ancestor directories of the input file until
one of .git, .hg, or dune-project is found. Since the .ocamlformat
config file is currently two directories higher than dune-project,
this fails. This diff moves the config file.

Reviewed By: jvillard

Differential Revision: D14694260

fbshipit-source-id: 2fb51bf30

.ocamlformat

@@ -1,4 +0,0 @@
-profile = ocamlformat
-let-binding-spacing = sparse
-margin = 100
-version = 0.9

.ocamlformat

@@ -0,0 +1 @@
+infer/src/.ocamlformat

infer/src/.ocamlformat

@@ -0,0 +1,4 @@
+profile = ocamlformat
+let-binding-spacing = sparse
+margin = 100
+version = 0.9