fix(ui): tweak animations

Cleanup props by removing 'in' which is passed in from parent.
Set dropdown max-height to be biggish, so that the dropdown doesn't need to expand more after animation is complete.
Drop margin, padding and border overrides so transitions can't alter the size of the dropdown.

ui/src/Components/Animations/DropdownSlide/index.css

@@ -1,15 +1,12 @@
 .components-animation-slide-enter,
 .components-animation-slide-appear {
-  opacity: 0.01;
+  opacity: 0.25;
   overflow: hidden;
   max-height: 0px;
-  border: 0;
-  padding: 0;
-  margin: 0;
 }
 .components-animation-slide-enter-active,
 .components-animation-slide-appear-active {
-  max-height: 500px; /* can't use auto here */
+  max-height: 2000px; /* can't use auto here */
   opacity: 1;
   transition-property: max-height, opacity;
   transition-duration: 0.15s;
@@ -17,16 +14,13 @@
 }
 
 .components-animation-slide-exit {
-  max-height: 500px; /* can't use auto here */
+  max-height: 2000px; /* can't use auto here */
   opacity: 1;
 }
 .components-animation-slide-exit-active {
-  opacity: 0.01;
+  opacity: 0.25;
   overflow: hidden;
   max-height: 0px;
-  border: 0;
-  padding: 0;
-  margin: 0;
   transition-property: max-height, opacity;
   transition-duration: 0.15s;
   transition-timing-function: ease-out;

ui/src/Components/Animations/DropdownSlide/index.js

@@ -7,7 +7,6 @@ import "./index.css";
 
 const DropdownSlide = ({ children, duration, ...props }) => (
   <CSSTransition
-    in={true}
     classNames="components-animation-slide"
     timeout={150}
     appear={true}

ui/src/Components/Animations/MountFade/index.js

@@ -7,7 +7,6 @@ import "./index.css";
 
 const MountFade = ({ children, duration, ...props }) => (
   <CSSTransition
-    in={true}
     classNames="components-animation-fade"
     timeout={150}
     appear={true}

ui/src/Components/Animations/MountModal/index.js

@@ -7,7 +7,6 @@ import "./index.scss";
 
 const MountModal = ({ children, duration, ...props }) => (
   <CSSTransition
-    in={true}
     classNames="components-animation-modal"
     timeout={200}
     appear={true}