Use "database" instead of "snapshot" in QLDocs

Author: How To Create An Engaging Facebook Story

go/ql/lib/semmle/go/Expr.qll

@@ -829,7 +829,7 @@ class ConversionExpr extends CallOrConversionExpr {
 /**
  * A function call expression.
  *
- * On snapshots with incomplete type information, type conversions may be misclassified
+ * On databases with incomplete type information, type conversions may be misclassified
  * as function call expressions.
  *
  * Examples:
@@ -2093,7 +2093,7 @@ class LabelName extends Name {
  * Holds if `e` is a type expression, as determined by a bottom-up syntactic
  * analysis starting with `TypeName`s.
  *
- * On a snapshot with full type information, this predicate covers all type
+ * On a database with full type information, this predicate covers all type
  * expressions. However, if type information is missing then not all type names
  * may be identified as such, so not all type expressions can be determined by
  * a bottom-up analysis. In such cases, `isTypeExprTopDown` below is useful.

go/ql/lib/semmle/go/controlflow/IR.qll

@@ -294,7 +294,7 @@ module IR {
  /**
  * An IR instruction that reads the value of a field.
  *
- * On snapshots with incomplete type information, method expressions may sometimes be
+ * On databases with incomplete type information, method expressions may sometimes be
  * misclassified as field reads.
  */
  class FieldReadInstruction extends ComponentReadInstruction {

go/ql/src/filters/ClassifyFiles.ql

@@ -1,6 +1,6 @@
 /**
  * @name Classify files
- * @description This query produces a list of all files in a snapshot that are classified as
+ * @description This query produces a list of all files in a database that are classified as
  * generated code, test code or vendored-in library code.
  * @kind file-classifier
  * @id go/file-classifier