chore(*): fix 'breif' typos

src/frontends/lean/info_manager.h

@@ -55,7 +55,7 @@ public:
         \remark #start_iteration unblocks it.
     */
     void block_new_info();
-    /** \breif Mark the start of a new information collection cycle.
+    /** \brief Mark the start of a new information collection cycle.
         It also enables new information to be added, i.e., it will undo
         the effect of #block_new_info.
     */

src/kernel/default_converter.h

@@ -15,7 +15,7 @@ Author: Leonardo de Moura
 #include "kernel/expr_pair.h"
 
 namespace lean {
-/** \breif Converter used in the kernel */
+/** \brief Converter used in the kernel */
 class default_converter : public converter {
 protected:
     typedef std::unordered_set<expr_pair, expr_pair_hash, expr_pair_eq> expr_pair_set;

src/library/class_instance_synth.h

@@ -41,10 +41,10 @@ optional<expr> mk_class_instance(environment const & env, io_state const & ios,
                                  name const & prefix, expr const & type, bool use_local_instances = true,
                                  unifier_config const & cfg = unifier_config());
 
-/** \breif Try to synthesize an inhabitant for (is_hset type) using class instance resolution */
+/** \brief Try to synthesize an inhabitant for (is_hset type) using class instance resolution */
 optional<expr> mk_hset_instance(type_checker & tc, io_state const & ios, list<expr> const & ctx, expr const & type);
 
-/** \breif Try to synthesize an inhabitant for (subsingleton type in the standard library, and hprop in the HoTT library)
+/** \brief Try to synthesize an inhabitant for (subsingleton type in the standard library, and hprop in the HoTT library)
     using class instance resolution */
 optional<expr> mk_subsingleton_instance(type_checker & tc, io_state const & ios, list<expr> const & ctx, expr const & type);