Fix failure in src/sage/structure/coerce_dict.pyx

[jaapspies]

Testing sage-9.0 on a Raspberry Pi 4B with Raspbian Buster

sage -t --long src/sage/structure/coerce_dict.pyx
**********************************************************************
File "src/sage/structure/coerce_dict.pyx", line 49, in sage.structure.coerce_dict
Failed example:
    len(LE)
Expected:
    1
Got:
    50
**********************************************************************
1 item had failures:
   1 of   9 in sage.structure.coerce_dict
    [296 tests, 1 failure, 91.00 s]
----------------------------------------------------------------------
sage -t --long src/sage/structure/coerce_dict.pyx  # 1 doctest failed
----------------------------------------------------------------------
Total time for all tests: 91.3 seconds
    cpu time: 90.7 seconds
    cumulative wall time: 91.0 seconds

Depends on #28941

Component: porting

Keywords: raspberry

Issue created by migration from https://trac.sagemath.org/ticket/28939

[mkoeppe]

comment:1

Moving tickets to milestone sage-9.2 based on a review of last modification date, branch status, and severity.

[fchapoton]

Changed keywords from none to raspberry

[dimpase]

comment:3

The reason for this error is handled on #28941

[dimpase]

Dependencies: #28941

[dimpase]

Changed author from jsp to none

[mkoeppe]

comment:5

Moving to 9.4, as 9.3 has been released.