Implicit default case in CF_WriteHistoryEntryToFile prevents full branch coverage

[skliper]

Checklist (Please check before submitting)

• I reviewed the Contributing Guide.
• I reviewed the CF README.md file to see if the feature is in the major future work.
• I performed a cursory search to see if the feature request is relevant, not redundant, nor in conflict with other tickets.

Is your feature request related to a problem? Please describe.
This will show up with the implicit default case uncovered since it's unreachable:

CF/fsw/src/cf_utils.c

Lines 190 to 206 in 593d61a

	for (i = 0; i < 3; ++i)
	{
	switch (i)
	{
	case 0:
	CF_Assert(h->dir < CF_Direction_NUM);
	snprintf(linebuf, sizeof(linebuf), "SEQ (%lu, %lu)\tDIR: %s\tPEER %lu\tCC: %u\t",
	(unsigned long)h->src_eid, (unsigned long)h->seq_num, CF_DSTR[h->dir],
	(unsigned long)h->peer_eid, (unsigned int)h->cc);
	break;
	case 1:
	snprintf(linebuf, sizeof(linebuf), "SRC: %s\t", h->fnames.src_filename);
	break;
	case 2:
	snprintf(linebuf, sizeof(linebuf), "DST: %s\n", h->fnames.dst_filename);
	break;
	}

Describe the solution you'd like
Add the default case explicitly

Describe alternatives you've considered
None

Additional context
None

Requester Info
Jacob Hageman - NASA/GSFC