I think that something is wrong with your custom fieldtype suggestType, .
Did you try to change it with something else (for example with text_general)?
I am not sure that charFilter solr.PatternReplaceCharFilterFactory works in solr 7. (And as I see it doesn`t replace in tags < and > ).
From my practice (solr 6-7) suggester works only with AnalyzingInfixLookupFactory (or without any lookupImpl):
<lst name="suggester">
<str name="name">mySuggesterContent</str>
<str name="field">pagebody_t</str>
<str name="suggestAnalyzerFieldType">text_suggester</str>
<str name="queryAnalyzerFieldType">text_suggester</str>
<str name="buildOnStartup">true</str>
<str name="buildOnCommit">true</str>
</lst>
<fieldType name="text_suggester" class="solr.TextField" positionIncrementGap="100" multiValued="false">
<analyzer type="index">
<tokenizer class="solr.WhitespaceTokenizerFactory"/>
<filter class="solr.StopFilterFactory" words="stopwords.txt" ignoreCase="true"/>
<filter class="solr.LowerCaseFilterFactory"/>
</analyzer>
<analyzer type="query">
<tokenizer class="solr.WhitespaceTokenizerFactory"/>
<filter class="solr.StopFilterFactory" words="stopwords.txt" ignoreCase="true"/>
<filter class="solr.SynonymFilterFactory" expand="true" ignoreCase="true" synonyms="synonyms.txt"/>
<filter class="solr.LowerCaseFilterFactory"/>
</analyzer>
</fieldType>