Replace relative imports in Cython files

src/sage/libs/gap/element.pyx

@@ -19,9 +19,9 @@ from cpython.object cimport Py_EQ, Py_NE, Py_LE, Py_GE, Py_LT, Py_GT
 from cysignals.signals cimport sig_on, sig_off
 
 from sage.libs.gap.gap_includes cimport *
-from .libgap import libgap
+from sage.libs.gap.libgap import libgap
 from sage.libs.gap.util cimport *
-from .util import GAPError
+from sage.libs.gap.util import GAPError
 from sage.cpython.string cimport str_to_bytes, char_to_str
 from sage.rings.integer_ring import ZZ
 from sage.rings.rational_field import QQ

src/sage/libs/gap/util.pyx

@@ -240,7 +240,7 @@ cdef initialize() noexcept:
         argv[11] = s1
         argv[4] = s1
 
-    from .saved_workspace import workspace
+    from sage.libs.gap.saved_workspace import workspace
     workspace, workspace_is_up_to_date = workspace()
     ws = str_to_bytes(workspace, FS_ENCODING, "surrogateescape")
     if workspace_is_up_to_date:

src/sage/libs/mpmath/ext_libmp.pyx

@@ -5,7 +5,7 @@ from sage.libs.mpmath.ext_impl cimport *
 from sage.libs.gmp.all cimport *
 
 # the next line is used by mpmath
-from .ext_impl import exp_fixed, cos_sin_fixed, log_int_fixed
+from sage.libs.mpmath.ext_impl import exp_fixed, cos_sin_fixed, log_int_fixed
 
 # Note: not thread-safe
 cdef MPF tmp1