LaTeX: fix figures in seealso and seealso inside table cell (#12598)

This also fixes unreported issues unrelated to the 7.4.0 release:

- (now old style "lightbox") admonitions render badly in tabulary,
- "heavybox" admonitions (they are all now but warning et al. were already) cause PDF crash if in tabulary and rendered badly if in tabular or longtable.
- figure in a table cell is not properly separated from immediately preceding text.

Co-authored-by: Adam Turner <9087854+aa-turner@users.noreply.github.com>

tests/test_builders/test_build_latex.py

@@ -158,21 +158,21 @@ def test_writer(app, status, warning):
 
     assert ('\\begin{wrapfigure}{r}{0pt}\n\\centering\n'
             '\\noindent\\sphinxincludegraphics{{rimg}.png}\n'
-            '\\caption{figure with align option}\\label{\\detokenize{markup:id9}}'
+            '\\caption{figure with align option}\\label{\\detokenize{markup:id10}}'
             '\\end{wrapfigure}\n\n'
             '\\mbox{}\\par\\vskip-\\dimexpr\\baselineskip+\\parskip\\relax' in result)
 
     assert ('\\begin{wrapfigure}{r}{0.500\\linewidth}\n\\centering\n'
             '\\noindent\\sphinxincludegraphics{{rimg}.png}\n'
             '\\caption{figure with align \\& figwidth option}'
-            '\\label{\\detokenize{markup:id10}}'
+            '\\label{\\detokenize{markup:id11}}'
             '\\end{wrapfigure}\n\n'
             '\\mbox{}\\par\\vskip-\\dimexpr\\baselineskip+\\parskip\\relax' in result)
 
     assert ('\\begin{wrapfigure}{r}{3cm}\n\\centering\n'
             '\\noindent\\sphinxincludegraphics[width=3cm]{{rimg}.png}\n'
             '\\caption{figure with align \\& width option}'
-            '\\label{\\detokenize{markup:id11}}'
+            '\\label{\\detokenize{markup:id12}}'
             '\\end{wrapfigure}\n\n'
             '\\mbox{}\\par\\vskip-\\dimexpr\\baselineskip+\\parskip\\relax' in result)
 
@@ -1591,7 +1591,9 @@ def test_latex_labels(app, status, warning):
 def test_latex_figure_in_admonition(app, status, warning):
     app.build(force_all=True)
     result = (app.outdir / 'projectnamenotset.tex').read_text(encoding='utf8')
-    assert r'\begin{figure}[H]' in result
+    assert 'tabulary' not in result
+    for type in ('caution', 'note', 'seealso', 'todo'):
+        assert f'{type} directive.\n\n\\begin{{figure}}[H]' in result
 
 
 def test_default_latex_documents():