Fix typos

This patch fixes several typos.

TrivialFix

Change-Id: Icd2ab913106107f2ed34408db9ef7fb1a255b076
diff --git a/manila_tempest_tests/tests/api/base.py b/manila_tempest_tests/tests/api/base.py
index 0395251..0adfbc1 100644
--- a/manila_tempest_tests/tests/api/base.py
+++ b/manila_tempest_tests/tests/api/base.py
@@ -752,7 +752,7 @@
                 error = abs(float(d1value) - float(d2value))
                 within_tolerance = error <= tolerance
             except (ValueError, TypeError):
-                # If both values aren't convertable to float, just ignore
+                # If both values aren't convertible to float, just ignore
                 # ValueError if arg is a str, TypeError if it's something else
                 # (like None)
                 within_tolerance = False