Upgrade dependencies, now that Pygments improved Crystal support

requirements.txt

@@ -7,22 +7,22 @@
 click==7.1.2              # via mkdocs, nltk
 future==0.18.2            # via lunr
 jinja2==2.11.2            # via mkdocs
-joblib==0.17.0            # via nltk
+joblib==1.0.0             # via nltk
 livereload==2.6.3         # via mkdocs
 lunr[languages]==0.5.8    # via mkdocs
 markdown==3.3.3           # via mkdocs, mkdocs-material, pymdown-extensions
 markupsafe==1.1.1         # via jinja2
 mkdocs-literate-nav==0.2.0  # via -r requirements.in
 mkdocs-material-extensions==1.0.1  # via mkdocs-material
-mkdocs-material==6.1.6    # via -r requirements.in, mkdocs-material-extensions
+mkdocs-material==6.2.4    # via -r requirements.in, mkdocs-material-extensions
 mkdocs-redirects==1.0.1   # via -r requirements.in
-mkdocs-section-index==0.2.1  # via -r requirements.in
+mkdocs-section-index==0.2.3  # via -r requirements.in
 mkdocs==1.1.2             # via -r requirements.in, mkdocs-literate-nav, mkdocs-material, mkdocs-redirects, mkdocs-section-index
 nltk==3.5                 # via lunr
-pygments==2.7.2           # via mkdocs-material
-pymdown-extensions==8.0.1  # via mkdocs-material
+pygments==2.7.4           # via mkdocs-material
+pymdown-extensions==8.1   # via mkdocs-material
 pyyaml==5.3.1             # via mkdocs
 regex==2020.11.13         # via nltk
 six==1.15.0               # via livereload, lunr
 tornado==6.1              # via livereload, mkdocs
-tqdm==4.53.0              # via nltk
+tqdm==4.56.0              # via nltk